Rin is the only character in vocaloid that is worth anything. The rest are uninteresting with the exception of Teto purely due to Mesmerizer with a cool animation. Miku is only interesting if she gets paired up with Rin. I doubt ill stick with your game though.
I do not find things like blowjobs or handjobs or other non sex stuff interesting at all and there is way too much of that. Too much cumming outside a swell, to the point i am going to skip all of it. If it doesnt involve the girls being fucked properly and given lots of creampies where they belong, ie the pussy, its not sex and it isnt interesting in the slightest. Ill never understand.