Momo Kyun Sword (Monster/Muscle Growth Transformation)

In the last Transformation Round-Up I featured a muscle-growth gif (found by Daymon) from an unknown anime and asked if anyone knew what show it from. An anonymous commenter, following on a tip left by the aptly named "Ms. Helpful," found the source.
It's from the anime Momo Kyun Sword and features a demon who becomes stronger whenever he eats women's panties. Here's the clip--there's further muscle growth toward the end:

Muscle growth fans should make sure to watch the other videos on this excellent channel!