I suddenly remember a not-vampire Webtoon dialogue where a redhead oneesan say to whitehair girl that she grow in skill. . and body as well. Imagining the onee-san with her futa duck enjoying a youthful developing body, I went to pixiv and search futa on female to see if can randomly find something similiar. 9 pages later nothing found, so I resort to danbooru. My search term
futanari -1girl white_hair -1boy red_hair -virtual_youtuber show 8 pages
initially I only search white_hair because in happenstance people only tag the sub one, it will appear. And minus search because vtuber return 2 pages (and mostly mouse anyway). I end up looking at Weiss a lot. Anyway here are my 5 finding in db t
post #1431178
post #4087586 (match the most)
post #2925215 (match the most)
post #2970261
post #3419249