User blog comment:B214/Question and Answers 4/@comment-4547267-20141031151941/@comment-58.186.163.109-20141031153708

No Issei made no swear like that. He's fine seeing Raynare got killed, he's fine seeing Kiba killed Freed, heck he's even fine seeing Xenovia vanquished Diodora's servants.

Issei goes for the kill if it's possible. He will kill even girls like Kuroka if she makes him angry or harms his comrades.