Well, Akira remains the least likeable character out of three, although she shows some serious signs of imporvement, she still is quite self-centred and half-sincere. Honestly, apart from her thoughts about Mayuki, it is her lack of sincerity that irks me, especially in contrast with two other girls genuineness. She was helping Mayuki in school, but didn't really care about her, it was more of an act seving her self-satisfaction. Also, while Mayuki heard Rin's story and came to feel sort of sympathy before kissing, Akira proceeds to do it even when she dislikes Mayuki. Now, in current situation, only Akira knows the true scope of their relationships, and, while she is closest to realizing the idea about triple relationship, she remains the furthest one to emotionally processing it( Mayuki loves Akira and likes Rin, Rin loves Mayuki and likes Akira as a friend,Akira loves Rin and has an uncertain attitude towards Mayuki).