I would say that my first hentai video, Akiba Girls, holds a special place in my heart. I found it on a video streaming site with no title and, years later when I started to download my collection, I desperately searched for it with vague memories in my mind.
In terms of my favorite hentai video, I would say Kanojo x Kanojo x Kanojo, mainly because it had a cute undertone and lovable characters.