Calling Goshuushou-sama Ninomiya-kun stunningly unimaginative would be a gross understatement. In three episodes the series has done nothing to endear itself; the only bait it has for its meagre hook is the fan-service which given the ropey art-style is perhaps not bait at all. Three episodes is enough to see exactly where this series is heading: it more or less started at rock bottom and each episode just gives it a new shovel to keep digging.
It's fair to say that series like Goshuushou-sama Ninomiya-kun are a dime a dozen, from Green Green to Amaenaideyo, mediocre fan-service is usually not a valid enough premise to warrant sitting through a series, be it 13 or 24 episodes or longer. Series such as Girls Bravo or Ikkitousen more or less perfected the rampant exposure of the female form, the former relying on increasingly racy content while the latter delving into classical Chinese literature; GSNK has neither the energy or the creativity to maintain interest beyond an initial viewing.
The premise is of a succubus who has little-to-no control over her powers of seduction which means she constantly attracts members of the opposite gender and elicits buried homosexual tendencies of the same gender. The foil to this hackneyed plot point is the titular Shungo Ninomiya who, while supposedly a gifted martial-artist, is charged with protecting the dim-witted succubus from the brainless male populace. Accompanying this is a devious incubus brother of Tsukimura, a loud-mouthed sister of Shungo and a prototypical yanderreko, Reika Hojo. The characters and situations are as trite and ill-conceived as the setup would lead one to believe, at no point is the raucous flailing anything more than tiring and the series seems to have been the subject of a 24 minute, titillation bypass operation.
Preceded by a short vignette of no worth other than to delay the interminable opening, it is only the ending which proves any value and even then, the mediocrity of the song is offset by the bright and kinetic animation introduced at the close of the third episode. Animation is consistently questionable, sometimes decent while other times making otherwise slim characters as thick and ugly as trees. The only notable name in the series is the animation studio, AIC Spirits, who gifted us with Tokyo Majin (both seasons) as well as Burn Up Scramble and the previously mentioned Girls Bravo; only Mai Kadowaki, who voices the busty succubus, has had any previously starring roles which isn't to say the other voice actors are bad, it's more indicative the of the overall quality.
There is nothing that can be recommended about Goshuushou-sama Ninomiya-kun; it sinks beneath adequacy into a turgid pit of clichés and boredom. It has no humour, no plot and no hope of doing anything other than being a stark reminder of how not to craft a show around fan-service.