I see user consensus seems to be keeping /h/ as /h/, so Haruhi wins.
But I'll say /h/ therefor officially comes from "H" (not "Hentai"), even if that itself originally comes from Hentai too, which I think but am not sure about comes from Hentai Seiyoku (変態性欲) which means "abnormal sexuality; sexual perversion" or "perversion" in the non-sexual way according to Jisho.org, not that I expect anyone to care this much about some naked drawn girls in their screens, I doubt even many Japanese bishoujo otaku know about it LOL