You are so right. Baam has all the reasons to get upset and a little crazy.
And that is the biggest question about Rachel: Why did she raised and teached not just every knowledge, but also moral values and concepts like friendship and respecting women to someone, if she hated him or was willing to abandon that person afterwards...? WHY!? I could understand if she did that to use Baam, make him attached to her and love her, so she could use his power to climb the tower. But the incoherence or contradiction is that: she doesn't want him to help her nor follow her... it doesn't make sense.
I really don't think Rachel hated Baam since the begining... maybe he loved him at first, but her envy grew so much it changed her feelings of friendship/or motherly love to disdain... ant that's why she tried to murder him...?
Yeah, I see a lot of her feelings about Baam being tied to her ideals of her own self-worthy and that SHE should be the one who was brought to the Tower and not Baam. And that is fed by her feelings of insecurity and envy.
I don't think she realized that working WITH Baam could have enabled her to get her goals. Or, this deal with FUG is really complicated and they made sure she excludes Baam.
And while I feel there is something fishy about her deal and her treatment of Baam...I'm leaning more on the idea that her jealousy turned her love into hate. It's not unheard of in friendships and families. Even parents have turned on their children out of envy.
He just wants to know why his mother/sister figure who RAISED him and taught him all about the world has not only abandoned him but tried to MURDER him. She was his whole world for many years.
He deserves answers.
Which is why I'm not shocked he's losing his cool. Can you imagine if the only person you knew you entire life and taught you how to read, write, and the world around you just abandoned you for no reason? Then after you went through all these trials you learn that they hated you and try to kill you and your friends?
And when you meet them once more and just want answers they just ask why you continue to chase after them and why you didn't just die. You realize they hate you and you don't understand why. Why raise you if they hated you? What is it that means so much to them that they could do this to you?
It is some serious mind fuckery.