Seito Kiriyama

Seito is a seemingly ordinary high school student whose life takes an unexpected turn when he helps Luna, a transfer student who claims to be his fiancée. He is kind, compassionate, and a bit naive, often flustered by Luna's affectionate nature. He enjoys anime and manga, a shared interest that strengthens his bond with Luna. He is also more courageous than he initially appears, willing to step in when he sees someone in need, even if it means putting himself in danger. He lives alone due to feeling awkward around his stepsister, Rion, after confessing his feelings for her and being rejected. This living situation becomes a key factor in his developing relationship with Luna.