Nursing Student Harem by Sandy Laine

Graham is a history student who works late on Saturday nights in the basement of the main library — mostly because nobody else is ever there.
Until Nina comes down to study, also. The brunette nursing student invites him to join her for a coffee when they kicked out at closing time. In the morning, he comes out of her room to find Rebekah, Nina’s red-head nursing student roommate, as well as Eden, her blonde roommate, also a nursing student. And there’s a strange caboose parked in the branches behind their rented house . . . .
As Graham discovers, each of them have different wants and needs — Nina likes to be pushed a bit, Rebekah has no shame, and Eden . . . well, Eden doesn’t have experience enough to know what she wants.
But the early 20s is a time for self-discovery, and the three girls and one guy discovery more than what’s usually allowed, and become, together, their best, or at least, most experienced, adult selves.

Previously released in serialized form as 10 separate stories, Nursing Student Harem is a realisticMFFF novel told in the male POV containing contemporary harem-like situations involving group menage scenes with multiple partners in slice-of-life scenarios with up to four characters at a time explicitly engaging in unprotected acts in often unconventional locations with emerging bisexual themes between the female characters.

Don’t say you weren’t warned . . . .