Sure. I've seen the shower scene. I'm talking permanent change & looking for a way to do so without sticking things in MC's butthole.

I assume that's just the way the game will be designed though, with rigid requirements to gain stats on that path which will undoubtedly involve more ass-play and gay sex. I'm not personally interested in feminization and planned to jump off the path once MC attained the embarrassingly perfect sized cuck cock, (one that squirts in 3 seconds and can't even reach the g-spot, let alone cervix

) trying to avoid as much gay/trans content for MC as possible on the way to get there. Though chastity and ruined orgasms are the opposite of what I like also (free my boy, let him jack!), I still kept him in a cage as much as possible in the hopes that it would contribute to the shrinkage without the need for more gay or trans content. The shrinkage looks to be 100% tied to feminization points though, unsurprisingly.
On how small it can get, I've dug through the image files though and it looks like MC's penis only shrinks one size of indeterminate length "seems to have gotten smaller" as of this update.