[Since any way he could describe that particular stretch could probably be misinterpreted quite a bit, Shun instead elects to show Ren what he means. Except it's pretty obvious that as soon as he lifts his leg back far enough that his foot is higher than his head, even if he is holding it firmly with one hand stretched back, and his back is curved with the motion almost as sharply as it had been on the beam earlier, this isn't a stretch that Ren is going to be able to do immediately either. It looks very much like a dance stretch, but it also looks very much like Shun absolutely does not give a damn as long as it works.]

Obviously it won't be this high for you from the start, but since you have to hold the leg with your hand anyway, it's not that hard to practice.