If you want a relationship route, take Tomoyo's or Nagisa's, they all will be better than Kyou's.
1/ "Oh hi, I like you, come over my house and fuck my sister"
2/ "Okay, they are getting along and my sister is less shy day per day, now I'll disappear, even though I'm Tomoya's best friend and it will all look normal"
3/ "I'll put hints that I love Tomoya"
4/ "No, I don't... Oh wait, yes I love you"
6/ SUDDEN END!
Yukine's route was more satisfactory