alterior motives
hidden motives in an action, such as witchcraft and sorcery
you guys always think i have alterior motives with my statuses
alterior motive
What your sweetheart may have if he asks you to visit a chapel wif him.
Be wary if your significant other requests your company while going to explore a chapel; he may actually have an alterior motive --- i.e., he hopes to have da two of you get hitched once you're inside da room wif him.