Catwoman rejects Penguin so he tries to murder her
She didn't just 'reject' him. This makes it sound like Catwoman was minding her own business and got approached and was just establishing boundaries.
It's best explained by revisiting how Catwoman approached Penguin to introduce herself to him:
She's clearly flaunting her sexuality (lying on his bed, literally showing him her pussy) and commenting on how 'chilly' it is, so he offers to warm her up, and she KICKS HIM IN THE CHEST.
skip to 3m in this clip - she starts pawing through his paperwork without asking (calls it 'enemy's list') so he stops her
then he asks why he should trust her, positing that maybe she's a screwball not worthy of being trusted
this prompts her to (3m33s) EAT HIS FUCKING BIRD
Penguin is obviously based (4m) and threatens to impale her pussy causing her to vomit up the bird.
Penguin is a hero who saves budgies from homicidal foids.
Catwoman tried to manipulate Penguin w/ her sexuality constantly giving him blueballs, yet kept rejecting him.
It's no wonder he got sick of it and gave her an airlift.
Though I really don't understand why he didn't just rape her, yeah.
If he's willing to kill her why wouldn't he be willing to cross the rape line and hatefuck her before sending her to her aerial doom?