Luke bought the Viper crossbow and then fired at his left hand three bolts. They didn't pierce many thanks to his high defense, and even though he also had a high resistance, their effects began to stack since Luke didn't pull them out. Fortunately, Luke's HP regeneration was pretty good, so it canceled the damage… It wasn't a pleasant experience, though. That being said, he couldn't think of anything else better to improve his defenses against that. It was a literal, no pain no gain. As expected, the others looked at him with concerned eyes, but Luke decided to keep at it. He didn't have time to worry too much about other people's opinions.
"You are doing something weird again," Rina said.
"Well, I have been neglecting my defensive skills, so I decided to improve them while I can," Luke said. "Just don't think too much about it.