BSS (Because I Loved Her First) is a genre depicting the situation where someone you secretly love ends up in a romantic relationship with another person before you could confess your feelings, leaving you unable to act. While similar to NTR (cuckold), since no official relationship existed, neither party is at fault—instead, the story highlights the protagonist's intense self-loathing and complex emotions. This work presents a classic BSS storyline, following a man who helplessly watches his closest friend begin a romantic relationship with the girl he loves, before he ever had the chance to confess. The protagonist's inner turmoil and emotional shifts are portrayed with great care, packed with elements designed to evoke deep empathy from viewers.