Ok, so, body expansion/weight gain isn't really my thing, That being said, I found this video to be very nicely done!
The drawings taken from the comic this is all from are great, can't argue with that. Correct me if I'm wrong, but what I got is that you, amongst other things, added the sounds and hired a very talented voice actress to give Hifumi a voice. And the final result turned out great, honestly!
To each their own, and objectively speaking, this was great, it's very enjoyable!
Kudos to the author of the comic, to you, AmpleExpansion, and of course, to the very competent voice actress, Trina Deuhart!
Keepin' an eye out for more! Bravo!