Hmm... I never got that option in the Bottom Logan route and by that I assumed it was also like that in my Top Logan route.. Both routes I have Ste with 1 heart.
Ok so I helped Ste again in the farm on my T!Logan route and now it is available, weird though, it isn't on the B!Logan route..
Oh right I got that threesome scene with Korg and the aphrodisiac, yes..