Oh god, I can just see Inui whipping out his extensive collection of threesome diagrams to illustrate all the possibilities and Kaidoh and Tezuka both turning bright, bright red ...

I had a few Inui/Tezuka screenshots but they all turned out annoyingly small, so I think I will have to steal my brother's computer again when he wakes up (if he ever wakes up!) and capture some new ones. Here's the best of the lot: