In a near-future Japan where same-sex marriage is legally recognized and socially unremarkable, gloomy office worker Ichigi Naoya has all but given up on finding a partner. He is a self-described introvert and otaku with low self-esteem, and his string of failed matchmaking attempts has only deepened his conviction that he is destined for a life alone. The one bright spot in his otherwise dreary existence is his colleague, Odajima, a charismatic, good-looking, and exceptionally capable marketing director who radiates charm and success. Ichigi nurses a hopeless crush on Odajima, fully aware that someone as ordinary and socially awkward as himself could never be reciprocated.

Ichigi resigns himself to a lifetime of fruitless one-sided love, but his mother pressures him into attending an arranged meeting with a potential marriage partner. Reluctantly, he agrees. To his utter shock, the person waiting at the designated venue is none other than Odajima. Even more bewildering, Odajima appears genuinely interested in pursuing the match and proposes that the two of them try living together for one year before deciding whether to marry. Ichigi is thrown into a maelstrom of disbelief and anxiety: how could a perfect, high-spec man like Odajima possibly want to tie himself to a gloomy, self-deprecating loser? Yet the prospect of sharing a home with his secret crush—and the promise of a better living situation rent-free—is too tempting to refuse.

What follows is a comedic and tender story of two men navigating a trial cohabitation. Ichigi, convinced that Odajima’s proposal must be either a practical joke or a momentary whim, struggles to understand why the man he admires would be so persistent. As they begin their shared life, Ichigi discovers that Odajima, for all his polished exterior, has his own quirks: he is terrible at waking up in the morning, cannot cook to save himself, and shows a vulnerable, unguarded side that he reveals only to Ichigi. These small, intimate revelations slowly chip away at Ichigi’s deep-seated belief that he is unlovable.

The narrative is built around the central conflict of Ichigi’s crushing lack of self-worth versus Odajima’s calm, methodical, and increasingly possessive affection. Odajima, far from being merely kind and supportive, reveals a subtly manipulative streak: the entire arranged meeting and the living-together proposal are part of a carefully orchestrated plan to win Ichigi over. He has loved Ichigi from a distance for years and has been patiently engineering circumstances to bring them together. This revelation dawns gradually on Ichigi, who at first cannot believe anyone, let alone a man as desirable as Odajima, would want him so badly.

Their relationship develops through alternating perspectives of comedy and tenderness. Ichigi’s internal monologue is filled with self-deprecating humor and panic as he stumbles through domestic life, while Odajima’s unwavering devotion and subtle control create a dynamic often described as a “see-saw game of obsessive love.” The physical aspect of their bond unfolds slowly, with Odajima taking great care to ensure Ichigi’s comfort and consent, building trust before they fully consummate their union. The pivotal moment comes when Odajima finally confesses his long-held feelings in a dramatic, heartfelt scene that affirms Ichigi’s worth and shatters his self-imposed isolation.

The story arcs from initial disbelief and awkward cohabitation through deepening emotional intimacy and eventual mutual confession, ending with the two officially marrying. Along the way, Ichigi’s transformation from a sour-faced, cynical loner into someone who can accept love and even express it in return is the emotional heart of the work. Odajima’s own arc reveals that beneath his perfect public persona lies a man who is just as deeply invested, lonely, and determined to claim the person he loves. The title “Sweet or Bitter Love” captures the dual nature of their journey: the sweetness of a fated bond and the bitterness of self-doubt that must be overcome before happiness can be embraced.