A Kite

Created by the same artist, they both have action and drama with female main characters. The plots are deep even with all the gun play. 

Mezzo Forte is a far superior, far less depressing, and much more entertaining version of the same story. That is the the better way to go as long as you skip the uncut version. 

Both shows have similar lead protagonists (a cute assassin girl who knows how to kick lots of ass). They also both have very tactile action scenes with heavy hitting, gruesome depictions of gore. The overall feel of each show is also very similar, probably in part because the lead artist and director is the same for both shows. 

Both are Hentai films made by the same studio. Each deal with a heavy emphasis on plot, in comparison to sex scenes. Both protagonists are involved in shady dealings. 

Both OVA's take place in the same universe. There are many similarities, especially in art and animation, which are both done by studio Arms. If you liked Mezzo Forte, you will definitely enjoy A Kite. 

Phantom Requiem and A Kite are both focused on male & female protagonists that forgot their past and only focus on their assassin job. Plot are pretty similar and both feature pretty impacting scenes. While Phantom focuses more on character development and soundtrack, A Kite is 1 hour of full action and incredible sakuga (it is labeled hentai but there are ~2 min of sex in the OVA). 

both are simmilar in the part where an orphan girl is recruited to kill people and becomes a skilled assasin, difference is phantom requiem is longer, with a lot more of character development while a kite more crude, blody and sexual 

Similar: Both involves a young female assassin that have a lost and forgotten past that they try to uncover as they fight for survival and the will to live, both also involve a love tie with a young male assassin that helps them regain their humanity, both can be dark and sometimes very cruel by treating the main female as an object rather than a person. Differences: Kite is far more violent with it's gore and blood where Phantom has hardly any blood plus Kite has it's explicit scenes (if you watched the uncensored version) , Phantom explores more on the importance of love and memories rather than just revenge alone. Overall: While I do personally enjoy Kite, Phantom is far superior in terms of it's story and characters, which I believe are the 2 most important things to have in any show or movie.  read more 

Anime that might be classified hentai. but they have an actual storyline, not just one to serve as an excuse for the plot. And considering both have assasing protagonists, there is also a focus on action scenes. 

They both have a plot driven story as the main focus and the hentai aspect as secondary  

Girl(s) trained by their masters to kill 

Both anime are starring tragic young girls abused as assasins, in the tradition of Luc Bresson's Nikita or Léon. In both anime, underage children are objectified, treated cruelly, and some are killed. A Kite goes much further regarding the degree of child abuse, depending on the cut version to explicit, hentai grade sexualized violence. The violence in Gunslinger Girl is more subtle and psychological, but it's eventual mind break effect is similar. In both, a lot of focus is placed on the psychology of the assasin girls, and their attempt to cope with the situation. Also, both have a hard to describe atmosphere of inevitablity, professionalism, and nagging doubt. read more 

For fans of Kite and Mezzo Forte, Cool Devices vol.07 "Yellow Star" is really worth checking out. Yasoumi Umetsu handled the character designs whom did the same for both Kite and Mezzo Forte. The storylines are similar and many state the fact that Yellow Star can be seen a s precursor to Kite. Cool Devices is episodic based and a little aged, but Vol.07 is worth checking out if you're a Kite/Mezzo Forte fan. 

Sure, it may be an odd recommendation, but Perfect Blue and Kite have a connection in characters being entangled in unholy situations, to the point where such come against their wills despite the efforts they can give forward. Perfect Blue does this with a stalker and hallucinations, a case of a mental attack. Kite does this with sexual moments and other disturbing elements, a case of physical attack. Both are pretty good in their respective genres, and something that deserves at the very least a try, more so for Kite than PB.  

Both have very similar character designs and art styles. The action scenes also feel very similar. However, the stories and the settings in each show is different. Kite is a modern day tale about professional killers, while Parasite Dolls is a near-future cyberpunk story about androids. 

Decimate. Kite and Elfen Lied both follow girls who have the ability to absolutely destroy their enemies. Kite's Sawa being an assassain. Elfen Lied's Lucy being a diclonius. In a way too, both of these girls are not free since one is being controlled, the other is a threat to humanity. Both of these MCs also try to create some happiness in their life with who they are paired with. Both are gorey and sexual anime made by the same studio, Arms. Be wary of Kite's hentai senses.