The protagonist, Kouma Akebonoin, is a barista working at a cafe on Minoba Island, a large resort destination.

Rumors had been circulating on the perpetually sunny island about strange drugs being traded recently, but he remained indifferent.

Around the time the rumors began, three tourists visited the island at the invitation of the island's owner. One was Utatsugu Mihiro, a bright, cheerful college girl radiating an extroverted vibe.

Another was OgawaKomado Rina, a young female teacher, the very picture of a well-bred lady.

And then there was Mamemuri Hazuki, a female doctor transferred from the mainland at the request of the island's clinic.

For some reason, all three become close to the protagonist, progressing into deep, intimate relationships.

──Because each of the three... no, four of them had their own secrets.

Set on an eternal summer resort island, a top-secret paradise story unfolds as the protagonist and three busty swimsuit heroines become entangled in a whirlwind of secrets and drugs!

[From official site]