Rent-A-Girlfriend

In Japan, the lonely have a new way out — online services that rent out dads, children, even girlfriends. When Kazuya's true love dumps him, he's just desperate enough to try it, and he's shocked at how cute and sweet his rental girlfriend turns out to be. But she wants to keep their "relationship" a secret, and there's a complication, she goes to his university, their grandmothers are in the same home, and they live next door to each other. Then Kazuya finds out she's not nearly as nice in "real life."

Source: Anime News Network Encyclopedia