Saenai Boku ga Kimi no Heya de Shiteiru Koto o Classmate wa Dare mo Shiranai - Vol. 4 Ch. 17

[peortega1]

I mean the audacity of this bitch and all but accepting it on the spot without informing MC is equally retarded. But shounen romance drama requires 50iq max as usual.

Is not 50 IQ max. Is Takai being, well, a shy and timid girl. A classic dandere.
A character who never would have dared to do what she did without being so notoriously abandoned by her mother and big sister -this is a big part of the LN vol. 2 plot-.
We are talking about the same girl who ordered Toyama doesn´t say a single word to her in class because she feared everyone would notice their FWB-status.
The interesting thing about her is how she combines, both now and after in the volumes 2 and 3 of the novel, this status of shy girl with being the dominatrix of Touyama -how you could see, for e.g., in chapters 13, 14, 15 and 16.5-. And probably because Touyama is other shy boy without friends and even more, very submissive and easy to dominate. The thing she calls him "Yuuki" (his name) while he calls her "Takai" (her surname) is a good proof of this disbalance of power between them and how she always takes the lead -and she will be doing it in the next LNs and the manga polygamic epilogue as adults-.
The low self-esteem of Takai is the reason why if you read her PoVs in the LN, you will notice how Yumi thinks she is not worthy from Touyama and just wishes "be useful for Yuuki". This is the reason why she can acts in a yandere way is only when the homewrecker cat is openly defying her (how she thinks Uehara is doing). Ishiyama deactived it when she says Touyama is not her type.

 

[peortega1]

I'll never get used to the new haircut. And yeah the ribbons make her look like a little girl which is bad.

Is more like the style of the mangaka who always made Takai look more childish and emotional than in the LN.
In the Light Novel art, even after cut hair and with the ribbons, she looks much more mature and adult:

 

[peortega1]

She combines this status of shy girl with being the dominatrix of Touyama -how you could see, for e.g., in chapters 13, 14, 15 and 16.5-.
And probably because Touyama is other shy boy without friends and even more, very submissive and easy to dominate. This disbalance of power between them and how she always takes the lead

This page of chapter 16.5 is a good example about how Yumi Takai is still the same as always even with the short hair and the ribbons, in fact, she looks even more dominant, androgynous and masculine here:

 

[Lex79]

Is more like the style of the mangaka who always made Takai look more childish and emotional than in the LN.
In the Light Novel art, even after cut hair and with the ribbons, she looks much more mature and adult:

Yeah, looks better, although I still consider it a downgrade.

 

[Nicoldemos]

They literally did nothing wrong. He's not "getting close to Uehara". It's the opposite, she's trying to get close to him. He's literally just being friendly and trying to not keep her at a distance, because he realized it's hurtful and not fair to do so.
Given the fact that he isn't in a relationship, and isn't pursuing anyone, he's not at fault in any way. And neither is Takai.
At most one could criticize him for not just shooting Uehara down clearly and unambiguously, but it's really not his responsibility.

"Not in a relationship"
Seriously. Having sex with a friend IS being in a relationship. Otherwise things wouldn't be so messy. MC would just end things with Takai and that's that. But he actually cares for her and she for him.
Second: Toyama went on a date with Uehara, and yes, that was a date. Do you really think you can have sex with someone AND go on dates with another person (without this person knows you sleeping with someone else) is normal? He should've said "no", and kept his first relationship, or "not now", and finish things first. But he did went to the date AND to having sex with Takai right after. Was because of confusion, because Takai makes him feel comfortable? Yes. Still doesn't give him a pass.
Also, Uehara thinks he's single so why wouldn't she try her best???