User blog comment:B214/Random Discussion/@comment-1359322-20140919201428/@comment-24421137-20140919202530

1. Issei would most likely enter a depressive state, only if Issei did not know who exactly did it. Probably would not be able to continue for a while until he is cheered up by a person who has went through the pain of loss, maybe Sairaorg, or maybe Vali, or could just be Rias.

2. Issei would probably start killing all of KB until he finally gets to the man who killed them, and then beats him to near death, until Rias begs him to stop as this was not him.

3. Probably not going to happen, after all loosing both your parents and your best friends were killed, nothing would be the same.