
This position is ideal to not just have an up-and-down fucking movement, but both partner can amplify their sensation by slowly rotating their basins. Also this position ensures a very good stimulation of the prostate, as well as an intense high contact. Plus the bottom can easily masturbate.

The Butterfly position can also be used to just masturbate without penetration, maybe as a warm-up activity or as a hot conclusion. In this case the two partners lay on the bed with their cock facing, which makes it possible to stroke them both with one hand only.
gayspirit.me/post/2824808163/19-the-butterfly-position