Inner penis

Does anyone do target that in their stretching? Is it worth the extra heating and work?

Not really, IMO. Your penis is tied to your body from the inside, very firmly. It could grow like the outer penis in theory, but it is ‘inner’ for a reason, so I guess it would be less responsive to stretching.

Is it in contradiction with fact that all stretching, pulling and hanging are affecting ligaments which are inner penis?

Very basic contradiction.

First, there is no contradiction: if you simply stretch your penis, you stretch every part. Second, ligaments are not ‘inner penis’. I don’t know where you gathered that info. The ‘inner penis’ are the CC, which diverge inside the body and get tied to the ischiopubis rami, one at left and one at right. The penis ligaments are the fundiform ligament and the suspensory ligament, and none of the both can be considered ‘inner penis’.