Hello, Limerence by Momo Yamaguchi

Mika is about to turn twenty-five, and all she has to show for it is a soul-sucking office job and a terminal case of virginity. Between the pervy salarymen she works with and the pretty boys she pines after, Mika is ready to explode. But it's summer in Tokyo, AKA peacock season. Time to strut her stuff. So when her certified Hot Girl bestie sends her the invite for an upcoming beach party, Mika clicks 'attending'. Just when she thinks real life is never going to live up to the wild fantasies her imagination cooks up, someone new catches her eye. It could be limerence, or the beginning of something much less one-sided.