Speaking as a lesbian, Yukari's hand on Yuyuko's clit + rubbing her own crotch against Yuyuko's ass can have this effect. Sometimes just pressure can do the trick, particularly if you're already turned on. Keep in mind that lady orgasms are generally centered on clitoral stimulation, not vaginal stimulation.
tristechan said: Speaking as a lesbian, Yukari's hand on Yuyuko's clit + rubbing her own crotch against Yuyuko's ass can have this effect. Sometimes just pressure can do the trick, particularly if you're already turned on. Keep in mind that lady orgasms are generally centered on clitoral stimulation, not vaginal stimulation.
Excellent lesson lady. Now I've learnt new knowlegdes.