Twelve-Winged Dark Seraphim
Dragon Bro tells him to follow the bell to the shelter because there's free power, Han Sen goes to the shelter and gets surprised that there's free power, and then damages himself in order to, for the first time ever, REJECT free power. He was TOLD before hand that going closer would unlock gene locks, he even asked Dragon Bro why he wasn't getting free power yet from just the bell tolls. He CHOSE to go into the palace, KNOWING that the creatures were there for the sole purpose of "CHEATING!" This reeks of another plot convenience. The main character does everything he can to get stronger, EXCEPT for when it's easier for the author for him to for the first time ever FIGHT AGAINST GETTING STRONGER! I'm confident that the whole crystallized body will turn into another massive buff with no downsides whatsoever, which doesn't bother me, what bothers me is the absurd logic that lead to the MC fighting the demonic energy to begin with.