I totally get what you mean but I also feel like throughout the chapters Jo already showed what he’s willing to do for Ian. Like Jo is literally a normal, non violent civilian who likes taking pictures and camping, but when Ian is involved he’s willing to put everything aside for him. Like when he saw that guy in the alley dying and didn’t calling him an ambulance, because Ian would get in trouble, he challenged TJ (whose a fucking violent gang leader) by saying he wanted Ian and should fuck off, he tracked Ian down to their camping spot they shared, and now he’s pulling up gun in hand and outnumbered by a bunch of gangsters with experience in fighting. Jo is a normal guy but his love for Ian is so strong he’s willing to sacrifice others and put himself in danger to save him
Okay listen, I know we don't want Jo hurt but, I need see him hurt so despite being hurt, we can see how resilient he is and how he can stand his ground. It will show us readers how more impactful Jo is as a character. The pure will and strength he's willing do for his love ones.