I am 100% for feminist Allen, but I still don't know how to make sense of Allen not calling out Bak's crush back when he was in the Asian Branch, and even using it as blackmail.
I guess it goes back to the bad writing that Bak crushing on Lenalee AND STALKING HER is “funny” and “ok”. Even if saying that it’s not unusual to have a 17 year old girl married off to someone multiple times her age, it is still pretty damn gross, especially if you take that into account that Lenalee basically grew up before Bak’s eyes. Even if he is attracted to her, he could go “no, this is wrong, I’m an adult and she’s a teen, it is wrong to think of her such way” but instead he fucking goes and even stalks her???
I’m not 100% sure what Hoshino’s intention was with that. As she has this view it is reflected in Allen as well. I can only think that Allen assumed that Bak had feelings for her, didn’t want to jump into conclusions. The Science Department keeping tabs on Exorcist is not unusual and those pic, while the fact that Bak hoards them to this degree is suspicious, they were not ‘provocative’, which is why he asked Bak if he liked her. I don’t know if he judged yes or no, but obviously he sees it as compromising enough to have a hold over Bak. Frankly I don’t know if Allen can identify sexual/romantic attraction as long as it’s not as obvious as Cross’s libido, he might not recognise it as attraction and doesn’t particularly care to find out, he has Bak under his thumb. In the Reverse Novel he did state he just joined the Order for info and seeing that the Order doesn’t match his view on the Akuma, he might have thought this is how he was going to keep closer tabs on the Order (this assuming that Allen is manipulative enough for it). He does call out on Cross hitting on Lenalee thankfully.
That being said, this is just an assumation. I don’t want to excuse or justify Allen’s silence. I have to admit that scene made and still makes me disappointed.