He was obviously in love with Orochimaru, thats why he never killed him and also always remembered him with pasion. Orochimaru knew it, thats why he runs from him, because he was to old for him and he likes the kids ( Sasuke, Kabuto... he was like Michael Jackson). Asuma was ashmade of it, but at the end he accepts it, thats why he said before die in the grave of his father "Im Proud to be born in the Sarutobi Clan". Kishi confirmed their love by killing the Third with a sword "from behind" and to give him pleasure enclosed him in a belly with Oro's hands rumbling him forever!!!