If you liked the Black Lagoon anime, the Anime-Planet community thinks you'd like:
Ellis is a young girl who possesses a strange ability to manipulate particles, and has an unfortunate case of amnesia. After accidentally killing a professor in the middle of an experiment, Ellis fled to Mexico and lived under the care of an old lady for many years, but her past has finally caught up with her; there's a price on her head, and men trying to capture her, dead or alive. She meets the bounty hunter Nadie, who befriends her and helps her escape; and together, they decide to travel south to Winay Marka, “The Land of Eternity”, to find clues about Ellis’ past. What’s the origin of Ellis’ powers, and what does “Project Leviathan” have to do with it?
Intensive gun-fights, shitty business, confusion. There is much more in common between Black Lagoon and El Cazarod de la Bruja than you can see at first sight! Both anime are much more enjoyable than you may think, especially if you don't like this particular genre. But don't turn your back! Some (already banal) themes are proposed in them. These include friednship, overcoming hardships. There are also similarities between the main characters - Rock (Black Lagoon) and Elis (El Cazador de la Bruja), but these are the similarities between the circumstances they are in that tie them together. Both Rock and Elis find their companions during experiencing hardships and in time when they most need help. After that they both enter a world they don't even expect to find.
For Kouta and Yuka, finding the bloody naked young girl on the beach would change their lives forever, for better or for worse. Unable to speak or function as a normal human being, she is named Nyu by the duo, and taken into their home in an effort to save her. But what neither teenager knows is that this innocent young girl is actually a killing machine -- an experiment gone terribly wrong -- and it is only a matter of time before the murderer in her awakens again...
Black lagoon and Elfen Lied are both meant for mature audience, although story telling and direction for black lagoon feels more polished and it also scores for having very good humorous quips, although as compared to Elfen Lied it may seem a bit pretentious.
Elfen Lied, after the bloodfest, feels a lot more cheesy. But by the end, it becomes quite serious.
In Essence, if you liked Black Lagoon, watch more than a few episodes of Elfen Lied to get the hang of it.
Much to the annoyance of Kei, he and his childhood friend Katou have died, having been torn apart by a train. But rather than finding themselves at the gates of heaven, the duo materialize in a room full of strangers and a giant black sphere known as GANTZ. As if dying once wasn’t bad enough, the occupants of the room are then forced to embark on dangerous missions to kill strange aliens; missions that very few return from. Now, Kei, Katou, and a well-endowed friend must fight for their freedom with an arsenal of guns, high powered suits, and a very low chance of survival.
The world we live in is a crazy one, indeed. But what happens if you step outside of that crazy world, what is waiting on the other side? Whether it is gunfire for fun, or an insane battle to save the human race of alien invasion, it is up to you. No matter you're choice, you will not be disappointed.
As Black Lagoon is filled with criminals spending their time fighting each other or stealing someone's money or even life, GANTZ is also full of dynamic battles with aliens for staying alive.
In the year 2034, two years after Major Motoko Kusanagi abruptly left Section 9, Togusa now leads the members of the elite counter cyber-terrorism team. After a hostage crisis, a mysterious ultra-wizard class hacker known only as the "Puppet Master" uncovers a vast conspiracy that leads to even the highest levels of government. When Kusanagi suddenly reappears, even the members of Section 9 begin to suspect that she may be in league with the mysterious "Puppet Master". Can Section 9 learn to trust the Major again before time runs out?
Henrietta is a young girl who works for a "welfare group" that does the government's dirty work. Cybernetically-enhanced and specially-trained, she is one of a group of elite hit-girls, remorseless killers with no memories of their past. Jose, her partner, has taken care of her since she was brought into the organization following the murder of her family, and struggles between his affection for her, and his opposing duty to his employer. But, time is running out.. for with each bullet they fire, Henrietta and the other girls lose a little more of their humanity.
There are some semilarities, both main characters are gun experts, but in Gunslinger Girls the characters are a bit emotioneless, but still the girls still have some relations of friendship between each other, in both anime there's a lot gun action, in both they take in dirty work from the bigshots and before the main story a lot of the charcters had different lifes from the ones they have now.