If you read Wild Rose maybe you'll understand the brother's reasons better.
And they don't say it, but I think it's only possible to bond with one beast, not many.
ive read all the books, and dont remember them saying you can only have one beast. the brother just assumes and goes to kill his brother. i dont get it.
On Wild Rose they explain that it's the duty of all the sane beasts to kill the crazy ones, because without their masters they just lost their minds and there's nothing the other could do besides stop their suffering by killing them. He doesn't just "goes to kill his brother".
yes, i remember that. but he was ready to kill his brother without finding out what was really going on. 0_0 thats what surprised me. he didnt bother trying to investigate.
Oh ok, I think I get your point now xD
Easy. Kiri thought there was just one master left (his) and Mao did not meet him yet. The grandma said that if a manbeast transforms without having meeting their master, they would go wild. Kiri then learns that a manbeast was spotted somewhere and he did go to investigate (in the hostel where his brother stayed at the beginning) and learnt that indeed it was his brother transforming without a master (again, he deduced this because Kiri's master was supposed to be the only one left)
good observation =) i didnt think about it that way
Why didnt the brother ask his master to become his brothers master as well? or can a beast master only control one specific beast? it just seemed odd how he just calmly was going to kill his brother. still a very beautiful manga. =)