Include relationship in session.user object?

import { customSession } from "better-auth/plugins";
 
export const auth = betterAuth({
    plugins: [
        customSession(async ({ user, session }) => {
            const roles = findUserRoles(session.session.userId);
            return {
                roles,
                user: {
                    ...user,
                    newField: "newField",
                },
                session
            };
        }),
    ],
});