A main character doesn't always have to act the way you like him to, but he has to keep the story interesting, and this manga does it quite well.
The characters are messed up, somewhat psychotic, full of problems, looking for love,... they're complex and not all that innocent.
I like how twisted it's all is, and it doesn't come out right away.... you have to keep reading to understand each character's motivation to act the way they do.
I really love how the love polygon works out, one character being secretly in love with another, and so on, but my peeve with this (always) is that people just don't tell each other how they feel straight out. But then again, if everyone just straight out told the person how they feel for them, we wouldn't have volumes over volumes of sweet heart tearing yaoi drama!
Yes, I don't particularly like some of the characters, they act foolish, careless and hurtful.
But nevertheless, Tsubaki, Tsumugi, Toudou and Yotsumi are all well thought out characters.
Tsubaki is struggling a lot with his love for his own twin brother, knowing it's not accepted but not letting go of his feelings. Tsumugi is a very lovable character, weak and innocent compared to his twin, and he cannot forget about his first love even though he tries to...
Everyone has their troubles to deal with.
There's also a new character, Yuuki Ibara, in volume 5, stirring up the whole thing a bit and becoming Tsumugi's love interest. Tsumugi does man up a bit at one point but stays an uke at heart haha. There's some interesting stuff still to happen in the remaining volumes!
The whole raping thing isn't good either BUT it does make for an interesting story here.
There's also a lot of "you're not giving it to me so I have to fuck someone else" going on.
That's just the way these characters are, they're messed up!
It's certainly not rose-colored romance here, but if you like twisted plots with messed up decisions and interesting characters then you might like this.