I'm really thinking the seme is like part zombie (based on the visual cues - his eyes, the "sew" marks of his tattoos, how parts of his body are hidden in blackout tattoos), and that kissing the uke, a human, is triggering (hence throwing up to get rid of the taste of flesh). With the way the other people in the community react to him, maybe they know he's half turned and just keep things on a need to know basis.
I'm really thinking the seme is like part zombie (based on the visual cues - his eyes, the "sew" marks of his tattoos, how parts of his body are hidden in blackout tattoos), and that kissing the uke, a human, is triggering (hence throwing up to get rid of the taste of flesh). With the way the other people in the community react to him, maybe they know he's half turned and just keep things on a need to know basis.