Uke just like he is with Kirishima.
you're definetely wrong. he was the seme. unstable emotions does not equate being uke at all(for example usagi and hiro san) In the novel yokosawa takafumi no bai, it was clearly stated that yokozawa has been touched down there(ass) in their first sex(zenxyokozawa). and takano was his first man..so. .isn't it obvious that yokozawa was the uke? and his attitude in the manga was very ukeish. so that's all.
Well, I don't have a concrete proof. But considering what was Takano's state was at that time, I think he would have done Yoko. And Yoko would have let him because he had feelings for Takano. When Zen and Yoko were having sex, Zen asked something like 'Have you done this before' and I clearly remember there was no comment from Yoko. It just felt like Yoko did was the uke with Takano. And Yoko is a major Tsundere and tsundere tends be usually a uke. I know its a stereotype but I think it fits more that Yoko was the uke.
And I read your earlier comment, that Takano and Yoko only touched each other. But Takano clearly mentioned to Ritsu that he slept with Yoko only once. Does touching each other equate to sleeping together?
Lately I was really confused for something.
Have you ever thought that Takano san have been an uke when he was with Yokozawa ??