Ueji's about to fight with the guy who can easily beat a bear with his bare hands. And hearing him say he'll break your spine... He literally and definitely will.
@KeiosKod https://mangadex.org/chapter/836590/19 The translators had a glossary for the tattoos. Hope it helps. You can cross check it with this face: https://mangadex.org/chapter/836590/10
@LLENN He likely projected himself on the kid to cope with whatever happend to him in the past. It'd be way too much of coincidence if the kid's name was the same as his.