diff --git a/packages/core/src/libraries/organization-invitation.ts b/packages/core/src/libraries/organization-invitation.ts
index e582ca6d042..1c867a6c751 100644
--- a/packages/core/src/libraries/organization-invitation.ts
+++ b/packages/core/src/libraries/organization-invitation.ts
@@ -174,7 +174,7 @@ export class OrganizationInvitationLibrary {
           });
 
           if (entity.organizationRoles.length > 0) {
-            await organizationQueries.relations.rolesUsers.insert(
+            await organizationQueries.relations.usersRoles.insert(
               ...entity.organizationRoles.map((role) => ({
                 organizationId: entity.organizationId,
                 organizationRoleId: role.id,
diff --git a/packages/core/src/libraries/user.ts b/packages/core/src/libraries/user.ts
index aaa2d026ca1..43996fbd127 100644
--- a/packages/core/src/libraries/user.ts
+++ b/packages/core/src/libraries/user.ts
@@ -138,7 +138,7 @@ export const createUserLibrary = (queries: Queries) => {
     const usersRoles = await findUsersRolesByUserId(userId);
     const rolesScopes = await findRolesScopesByRoleIds(usersRoles.map(({ roleId }) => roleId));
     const organizationScopes = findFromOrganizations
-      ? await organizations.relations.rolesUsers.getUserResourceScopes(
+      ? await organizations.relations.usersRoles.getUserResourceScopes(
           userId,
           resourceIndicator,
           organizationId
@@ -295,7 +295,7 @@ export const createUserLibrary = (queries: Queries) => {
       }))
     );
     if (data.length > 0) {
-      await organizations.relations.rolesUsers.insert(...data);
+      await organizations.relations.usersRoles.insert(...data);
     }
 
     return jitOrganizations;
diff --git a/packages/core/src/oidc/grants/refresh-token.test.ts b/packages/core/src/oidc/grants/refresh-token.test.ts
index 9839b4c802f..55110e6b58d 100644
--- a/packages/core/src/oidc/grants/refresh-token.test.ts
+++ b/packages/core/src/oidc/grants/refresh-token.test.ts
@@ -317,7 +317,7 @@ describe('organization token grant', () => {
 
     Sinon.stub(tenant.queries.organizations.relations.users, 'exists').resolves(true);
     Sinon.stub(tenant.queries.applications, 'findApplicationById').resolves(mockApplication);
-    Sinon.stub(tenant.queries.organizations.relations.rolesUsers, 'getUserScopes').resolves([
+    Sinon.stub(tenant.queries.organizations.relations.usersRoles, 'getUserScopes').resolves([
       { tenantId: 'default', id: 'foo', name: 'foo', description: 'foo' },
       { tenantId: 'default', id: 'bar', name: 'bar', description: 'bar' },
       { tenantId: 'default', id: 'baz', name: 'baz', description: 'baz' },
diff --git a/packages/core/src/oidc/grants/refresh-token.ts b/packages/core/src/oidc/grants/refresh-token.ts
index d481cf13ee5..9bb2d232c45 100644
--- a/packages/core/src/oidc/grants/refresh-token.ts
+++ b/packages/core/src/oidc/grants/refresh-token.ts
@@ -338,7 +338,7 @@ export const buildHandler: (
     /* === RFC 0001 === */
     const audience = buildOrganizationUrn(organizationId);
     /** All available scopes for the user in the organization. */
-    const availableScopes = await queries.organizations.relations.rolesUsers
+    const availableScopes = await queries.organizations.relations.usersRoles
       .getUserScopes(organizationId, account.accountId)
       .then((scopes) => scopes.map(({ name }) => name));
 
diff --git a/packages/core/src/queries/organization/role-application-relations.ts b/packages/core/src/queries/organization/application-role-relations.ts
similarity index 96%
rename from packages/core/src/queries/organization/role-application-relations.ts
rename to packages/core/src/queries/organization/application-role-relations.ts
index 58eda8fbea8..f576732c1fa 100644
--- a/packages/core/src/queries/organization/role-application-relations.ts
+++ b/packages/core/src/queries/organization/application-role-relations.ts
@@ -9,7 +9,7 @@ import { type CommonQueryMethods, sql } from '@silverhand/slonik';
 import RelationQueries from '#src/utils/RelationQueries.js';
 import { convertToIdentifiers } from '#src/utils/sql.js';
 
-export class RoleApplicationRelationQueries extends RelationQueries<
+export class ApplicationRoleRelationQueries extends RelationQueries<
   [typeof Organizations, typeof OrganizationRoles, typeof Applications]
 > {
   constructor(pool: CommonQueryMethods) {
diff --git a/packages/core/src/queries/organization/index.ts b/packages/core/src/queries/organization/index.ts
index 84a40dbdc74..1d4d161c08e 100644
--- a/packages/core/src/queries/organization/index.ts
+++ b/packages/core/src/queries/organization/index.ts
@@ -32,11 +32,11 @@ import { TwoRelationsQueries } from '#src/utils/RelationQueries.js';
 import SchemaQueries from '#src/utils/SchemaQueries.js';
 import { conditionalSql, convertToIdentifiers } from '#src/utils/sql.js';
 
+import { ApplicationRoleRelationQueries } from './application-role-relations.js';
 import { EmailDomainQueries } from './email-domains.js';
-import { RoleApplicationRelationQueries } from './role-application-relations.js';
-import { RoleUserRelationQueries } from './role-user-relations.js';
 import { SsoConnectorQueries } from './sso-connectors.js';
 import { UserRelationQueries } from './user-relations.js';
+import { UserRoleRelationQueries } from './user-role-relations.js';
 
 /**
  * The schema field keys that can be used for searching roles.
@@ -285,9 +285,8 @@ export default class OrganizationQueries extends SchemaQueries<
     ),
     /** Queries for organization - user relations. */
     users: new UserRelationQueries(this.pool),
-    // TODO: Rename to `usersRoles`
     /** Queries for organization - organization role - user relations. */
-    rolesUsers: new RoleUserRelationQueries(this.pool),
+    usersRoles: new UserRoleRelationQueries(this.pool),
     /** Queries for organization - application relations. */
     apps: new TwoRelationsQueries(
       this.pool,
@@ -295,9 +294,8 @@ export default class OrganizationQueries extends SchemaQueries<
       Organizations,
       Applications
     ),
-    // TODO: Rename to `appsRoles`
     /** Queries for organization - organization role - application relations. */
-    rolesApps: new RoleApplicationRelationQueries(this.pool),
+    appsRoles: new ApplicationRoleRelationQueries(this.pool),
     invitationsRoles: new TwoRelationsQueries(
       this.pool,
       OrganizationInvitationRoleRelations.table,
diff --git a/packages/core/src/queries/organization/role-user-relations.ts b/packages/core/src/queries/organization/user-role-relations.ts
similarity index 98%
rename from packages/core/src/queries/organization/role-user-relations.ts
rename to packages/core/src/queries/organization/user-role-relations.ts
index c3430fae40f..7f3573c3262 100644
--- a/packages/core/src/queries/organization/role-user-relations.ts
+++ b/packages/core/src/queries/organization/user-role-relations.ts
@@ -16,7 +16,7 @@ import { sql, type CommonQueryMethods } from '@silverhand/slonik';
 import RelationQueries from '#src/utils/RelationQueries.js';
 import { conditionalSql, convertToIdentifiers } from '#src/utils/sql.js';
 
-export class RoleUserRelationQueries extends RelationQueries<
+export class UserRoleRelationQueries extends RelationQueries<
   [typeof Organizations, typeof OrganizationRoles, typeof Users]
 > {
   constructor(pool: CommonQueryMethods) {
diff --git a/packages/core/src/routes/interaction/actions/submit-interaction.ts b/packages/core/src/routes/interaction/actions/submit-interaction.ts
index 69576241904..3c37e9e8035 100644
--- a/packages/core/src/routes/interaction/actions/submit-interaction.ts
+++ b/packages/core/src/routes/interaction/actions/submit-interaction.ts
@@ -178,7 +178,7 @@ async function handleSubmitRegister(
     // This is only for Cloud integration tests and data alignment, OSS still uses the legacy Management API user role.
     const organizationId = getTenantOrganizationId(defaultTenantId);
     await organizations.relations.users.insert({ organizationId, userId: id });
-    await organizations.relations.rolesUsers.insert({
+    await organizations.relations.usersRoles.insert({
       organizationId,
       organizationRoleId: getTenantRole(TenantRole.Admin).id,
       userId: id,
diff --git a/packages/core/src/routes/organization/index.application-role-relations.ts b/packages/core/src/routes/organization/index.application-role-relations.ts
index 6de2a909097..b9e3f6702ae 100644
--- a/packages/core/src/routes/organization/index.application-role-relations.ts
+++ b/packages/core/src/routes/organization/index.application-role-relations.ts
@@ -44,7 +44,7 @@ export default function applicationRoleRelationRoutes(
     async (ctx, next) => {
       const { id, applicationId } = ctx.guard.params;
 
-      const [totalCount, entities] = await organizations.relations.rolesApps.getEntities(
+      const [totalCount, entities] = await organizations.relations.appsRoles.getEntities(
         OrganizationRoles,
         {
           organizationId: id,
@@ -71,7 +71,7 @@ export default function applicationRoleRelationRoutes(
       const { id, applicationId } = ctx.guard.params;
       const { organizationRoleIds } = ctx.guard.body;
 
-      await organizations.relations.rolesApps.insert(
+      await organizations.relations.appsRoles.insert(
         ...organizationRoleIds.map((organizationRoleId) => ({
           organizationId: id,
           applicationId,
@@ -97,7 +97,7 @@ export default function applicationRoleRelationRoutes(
       const { id, applicationId } = ctx.guard.params;
       const { organizationRoleIds } = ctx.guard.body;
 
-      await organizations.relations.rolesApps.replace(id, applicationId, organizationRoleIds);
+      await organizations.relations.appsRoles.replace(id, applicationId, organizationRoleIds);
 
       ctx.status = 204;
       return next();
@@ -113,7 +113,7 @@ export default function applicationRoleRelationRoutes(
     async (ctx, next) => {
       const { id, applicationId, organizationRoleId } = ctx.guard.params;
 
-      await organizations.relations.rolesApps.delete({
+      await organizations.relations.appsRoles.delete({
         organizationId: id,
         applicationId,
         organizationRoleId,
diff --git a/packages/core/src/routes/organization/index.applications.openapi.json b/packages/core/src/routes/organization/index.applications.openapi.json
index afa802114f7..23bebb126cf 100644
--- a/packages/core/src/routes/organization/index.applications.openapi.json
+++ b/packages/core/src/routes/organization/index.applications.openapi.json
@@ -148,7 +148,10 @@
             "description": "The role was removed from the application in the organization successfully."
           },
           "422": {
-            "description": "The role could not be removed. The role may not exist."
+            "description": "The application is not associated with the organization."
+          },
+          "404": {
+            "description": "Cannot find the record to delete."
           }
         }
       }
diff --git a/packages/core/src/routes/organization/index.jit.email-domains.ts b/packages/core/src/routes/organization/index.jit.email-domains.ts
index 37e79f65dc9..fc5a28916e5 100644
--- a/packages/core/src/routes/organization/index.jit.email-domains.ts
+++ b/packages/core/src/routes/organization/index.jit.email-domains.ts
@@ -72,7 +72,7 @@ export default function emailDomainRoutes(
     `${pathname}/:emailDomain`,
     koaGuard({
       params: z.object({ ...params, emailDomain: z.string().min(1) }),
-      status: [204],
+      status: [204, 404],
     }),
     async (ctx, next) => {
       const { id, emailDomain } = ctx.guard.params;
diff --git a/packages/core/src/routes/organization/index.ts b/packages/core/src/routes/organization/index.ts
index 9c37345655b..7b68a455f14 100644
--- a/packages/core/src/routes/organization/index.ts
+++ b/packages/core/src/routes/organization/index.ts
@@ -129,7 +129,7 @@ export default function organizationRoutes<T extends ManagementApiRouter>(
       const { id } = ctx.guard.params;
       const { userIds, organizationRoleIds } = ctx.guard.body;
 
-      await organizations.relations.rolesUsers.insert(
+      await organizations.relations.usersRoles.insert(
         ...organizationRoleIds.flatMap((roleId) =>
           userIds.map((userId) => ({ organizationId: id, organizationRoleId: roleId, userId }))
         )
diff --git a/packages/core/src/routes/organization/index.user-role-relations.ts b/packages/core/src/routes/organization/index.user-role-relations.ts
index 2afa1989e33..fa6898f9388 100644
--- a/packages/core/src/routes/organization/index.user-role-relations.ts
+++ b/packages/core/src/routes/organization/index.user-role-relations.ts
@@ -43,7 +43,7 @@ export default function userRoleRelationRoutes(
     async (ctx, next) => {
       const { id, userId } = ctx.guard.params;
 
-      const [totalCount, entities] = await organizations.relations.rolesUsers.getEntities(
+      const [totalCount, entities] = await organizations.relations.usersRoles.getEntities(
         OrganizationRoles,
         {
           organizationId: id,
@@ -69,7 +69,7 @@ export default function userRoleRelationRoutes(
       const { id, userId } = ctx.guard.params;
       const { organizationRoleIds } = ctx.guard.body;
 
-      await organizations.relations.rolesUsers.insert(
+      await organizations.relations.usersRoles.insert(
         ...organizationRoleIds.map((roleId) => ({
           organizationId: id,
           organizationRoleId: roleId,
@@ -93,7 +93,7 @@ export default function userRoleRelationRoutes(
       const { id, userId } = ctx.guard.params;
       const { organizationRoleIds } = ctx.guard.body;
 
-      await organizations.relations.rolesUsers.replace(id, userId, organizationRoleIds);
+      await organizations.relations.usersRoles.replace(id, userId, organizationRoleIds);
 
       ctx.status = 204;
       return next();
@@ -109,7 +109,7 @@ export default function userRoleRelationRoutes(
     async (ctx, next) => {
       const { id, roleId, userId } = ctx.guard.params;
 
-      await organizations.relations.rolesUsers.delete({
+      await organizations.relations.usersRoles.delete({
         organizationId: id,
         organizationRoleId: roleId,
         userId,
@@ -130,7 +130,7 @@ export default function userRoleRelationRoutes(
     async (ctx, next) => {
       const { id, userId } = ctx.guard.params;
 
-      const scopes = await organizations.relations.rolesUsers.getUserScopes(id, userId);
+      const scopes = await organizations.relations.usersRoles.getUserScopes(id, userId);
 
       ctx.body = scopes;
       return next();
diff --git a/packages/core/src/routes/organization/index.users.openapi.json b/packages/core/src/routes/organization/index.users.openapi.json
index 5580e0b450a..174469303b0 100644
--- a/packages/core/src/routes/organization/index.users.openapi.json
+++ b/packages/core/src/routes/organization/index.users.openapi.json
@@ -190,8 +190,11 @@
           "204": {
             "description": "The role was removed from the user successfully."
           },
+          "422": {
+            "description": "The user is not a member of the organization."
+          },
           "404": {
-            "description": "The user is not a member of the organization; or the user does not have the role."
+            "description": "Cannot find the record to delete."
           }
         }
       }
diff --git a/packages/integration-tests/src/tests/api/organization/organization-application.test.ts b/packages/integration-tests/src/tests/api/organization/organization-application.test.ts
index c231e1f915c..36ea50566bb 100644
--- a/packages/integration-tests/src/tests/api/organization/organization-application.test.ts
+++ b/packages/integration-tests/src/tests/api/organization/organization-application.test.ts
@@ -112,7 +112,7 @@ devFeatureTest.describe('organization application APIs', () => {
       );
 
       const response = await organizationApi
-        .addApplicationRoles(organization.id, '0', [application.id])
+        .addApplicationRoles(organization.id, application.id, ['0'])
         .catch((error: unknown) => error);
       assert(response instanceof HTTPError);
       expect(response.response.status).toBe(422);