A fling where you exclusively hang out on Sundays. Typical activities include sex, sleeping, snuggling and snacks.
So you're free to chill, date and wild out from Monday-Saturday but get all the best benefits of a relationship come Sunday.
Like a situationship but specific to Sunday.
Yo I met the perfect match on Hinge. No more Sunday scaries and I still get my sweet freedom thanks to our Sunday situation.