"It'd be regretful for me to grind you to pieces, but that's enough." or something like that. In another word (didn't read FT 160 yet, but will probably do it tonight), Zero enjoyed his fight with Natsu, since Natsu is pretty strong, but since he has to destroyed him, he'd surely regret that he can't enjoying fighting with him more than this. Something like that. I can't really explain it well either...(the Thai phrase did jump into my mind...but certainly not a good English phrase... ._.")