Kowaku no Toki

- Both are a Excellent Hentai with a male lead trying to help a pretty girl in distress. In Miharu, it's to help Miharu regain her memory. In Kowaku, it's to free Yukino from the Bull's Curse - Both got extremely Pretty + Cute Girls - Both got Sexy Sex Scenes, but Kowaku in addition has some torture and contains bestiality 

Now this is your Excellent Damsel in Distress Hentai! In Kowaku, Yukino is held captive by the Bull’s Curse. In Shishunki, Rina is held captive by thugs. Fair warning, Kowaku got Bestiality and some torture, but it’s so Hot! 

Netorare and the lady is stolen by a ugly servant 

Both are kinky and hardcore and have rape and bondage of a female. 

If you have a taste of evil fetish, this will appeal to you. - Both are the BEST Hentai I've seen with bestiality. In Kowaku, it's sex with a Bull. In Haitoku, it's sex with a Dog. - Both Hentai has a girl trapped into a situation of submission, but in Kowaku, there's a guy trying to save the girl. - Both Hentai has bondage. Difference is Kowaku has some torture, while Haitoku has some scat. 

PoRo were originally Amour whom were originally Himagin or something, it's a weird complication but essentially you can see PoRo's signature style shine through back in Ikusa Otome Valkyrie here, though the character designs are refreshingly a bit different. Anyways if you're a fan of them but tired of the NTR tropes and enjoy the darker tastes of hentai, look no further. Lots of bondage, full on bestiality (two bull scenes), large insertions and impreg in Kowaku no Toki, whereas Ikusa Otome Valkyrie is still to this day in my mind among the best monster rape hentai out there, the sequels don't compare to the original here. Nonstop banging with sex scene after sex scene like a lot of PoRo's stuff. Excellent stuff and these two along with the original Inyouchuu The Animation really make me wish PoRo did darker stuff more regularly.  read more 

Although different studio's for their anime adaptations, both series originate from the sadistic Tinkerbell mastermind Aojiru. The content is not as extreme as the original h-games, but still hardcore enough that these push the boundaries. Massive insertions and instances of bug impreg/birthing in Inyouchuu Shoku, while the main girl in Kowaku (Yukino) gives birth to a baby bull, although it's invisible and censored. Regardless Kowaku has full on BULL action, that's no horse folks (pulling info from the game here). Inyouchuu Shoku is a tentacle fest with the biggest tentacles and the crazy demon Meioki who wins, whereas Kowaku is sadistic with the beasty action and other extreme genres. If vanilla hentai with boring men around the place bores you, then these are for you. Girls get nothing but tentacles, demons, and bugs in Shoku, and a huge bull in Kowaku! Hell yeah. Check them out if you like awesome dark h-anime.  read more 

if you're looking for some hardcore stuff, like dark, makes you question your sanity, has a large shock factor and some plot, material then both are extremely similar. one can say that these are akin to sexual torture. sure, you could be pointed out to other anime that have tentacles but neither of these use those cliches, they present situations that are impressively far worse. not for the faint of heart