He uses the same words to describe his feelings for Aya the page before, so nope not decisive.
So, Yuu is not decisive only because he said he would like have a threesome? Anyway, he used the same words to describe his PAST feelings for Aya. Past tense. Yuu is not fault about Hikari being a coward who is unable to ask directly him about his PRESENT feelings for Yami.
But again, he is the man, and...
Damn, even Haru and Yuki are reacting in this chapter upon the basis of "you are the man here", but again, they are in her right because they are common traditional Japanese girls, but here in Dex, almost everybody are feminists and progressives saying the same shit who any patriarchal Old Boomer dude would say it.
PS. And yes, everyone here are blaming Yuu just because he said he wanted to make a threesome.