That's problematic for a whole dif reason. Picture he dies and is reborn, mc would be a baby and each time the seme would have to wait until he's an adult and reintroduce himself, just for the mc to die again and the process repeat itself. That's a tragedy
That’s only if you see death as a bad thing. But if he lives fulfilling, peaceful lives under the snake god’s watch each time, isn’t that enough? Afterall, death (of the mortal flesh) looks very different to a god, it’s only our human perspective that makes us see it as a tragedy rather than a cycle. He could counter the problematic nature of it by just making Taesun gradually remember his past lives as he gets older
Idk, isn’t it more ‘realistic’ and romantic just to find Taesun each time he reincarnates the babies aren’t gonna stay little forever anyway