I like the "happy sex" board of wakachan, but there's never enough of it there. I guess people on the internet really do like getting off as opposed to seeing people express their emotional bond in a physical manner.
Or is it because it would only remind the otaku of what they're missing?
You are thinking too far into it. Happy sex is rare indeed, but it has nothing to do with reminding otakus about something. It's just that an otaku craves for lust more than for love. Screaming, steamy action, pushing it to extremes with a retarded face on, something like that is far better suited for expressing excitement. Love just won't do. Though I have to admit its nice for a change once in a while.
I concur with Mazryonh. The sentimental factor delivers a great deal of appeal in Hentai, which is why pictures and moments like this are greatly appreciated.
I am something of an Otaku myself and I think that love+sex = happiness.
Love + Being Loved in Return = Happiness. Sex is a bonus.
I disagree. Sex is not a bonus, but a variable. Love + Being loved x Sex = Happiness. The proof for this lies in the fact that sexless relationships almost always lead to cheating for one or both parties. Ergo, sex is super important for a long-lasting, happy relationship.