In the midst of preparing for university exams, Shouichi Kamita grapples with the universal conundrum of love, a perplexing emotion that strikes at any age. As he navigates his teenage years, three potential romantic interests capture his attention: the lively and teasing Hikari Tsuneki, who conceals a gentle side beneath her playful facade; the introverted gamer Tooru Miyamae, who struggles with social interactions; and Kyouko Touno, Shouichi's childhood friend and avid fan of shoujo manga, whose youthful antics sometimes overshadow her maturity. Through three distinct story arcs, Seiren delves into Shouichi's evolving relationships with these girls, as initial sparks of attraction gradually evolve into something truly enchanting.