Ishura is absolute nonsense... but entertaining nonsense.
TBH I'm surprised nobody has suggested stuff like spider-chan or vivy. But if he's watching them dubbed, there's a very real chance you'd want to put your eyes out based on the main char's voices alone. I wouldn't know, dubbed is a war crime.
I love battle royale movies and shows and they are all ridiculous fun. I would have mentioned Jigokuraku but I think he would have thought that too ridiculous. I also tried to focus on pure action series with very little cutesy but those are both top notch.
I had a resident who only watched dubbed. I don't miss him, lol?