Boku wa Tomodachi ga Sukunai: Relay Shousetsu wa Ketsumatsu ga Hanpanai

Some OVAs seek to give a series a greater sense of conclusion. Other OVAs are an excuse to turn a series into Hentai. This OVA doesn't seem to quite do either of those. Haganai's OVA is simply another episode, and one which neither advances the story line nor brings any character development to the table; it's purely fan service and I emphasize- for fans only. If you aren't unhealthily attached to any of the main characters in the main series, then this may not be worth your time.

Animation:
The animation quality is on par with the main series, though you're going to get some really wacky ... outfits and (very ecchi) mechs? There's a serious effort to parody other series, which I'll let the viewed discover for him/herself, sometimes embedded in the visuals. The series' only absolution is the liberal airtime given to Sena. As in the main series, expect significant ecchi - though this one goes pretty close to full H.

Sound:
You have the same OP as the parent series and the VA cast is identical as well. They add a new ED sung by the cast, which has an annoyingly-repetitive main melody.

Story:
We find our loners club on a typical day where they decide to take turns writing a single short story. This soon turns into everyone's individual fantasy involving Kodaka as they churn out the most in-cohesive story ever written. While certain parts are amusing, the overall plot is quite lame and contributes absolutely nothing to the overall series. I'll admit I'm a bit biased as I was hoping for a bit more relevance given the less-than-stellar ending to the parent series.

Character:
While each character does get air time, their interactions are as you would expect from the main series. Their interactions are still fun to watch, but I think the series missed a great opportunity to give some more background on Rika/Yukimura.

Value:
Other than for base entertainment and/or fan service, this doesn't add much to the parent franchise, for dedicated fans of the main show only.