Aya, Omi, Ken and Yoji are four seemingly normal high school boys, who make up an elite assassin group known only as Weiss. The hits involve taking out corporate businessmen and corrupt politicians; however, trouble arises during a routine job, when Weiss clashes with a rival gang of assassins, Schwarz. With Schwarz in the way, they will reach the limits of their elite skills while trying to defeat their ultimate target: the Takatori family...
A devastating earthquake strikes Tokyo, leaving the city in ruins. Man's only hope is to use boomers, an artificial humanoid form. Everything seems perfect until some of the boomers go crazy and start killing people. The only hope of stopping them is the Knight Sabers, a group of 4 female heroes in form-fitting power suits, with which they can perform amazing feats of strength and agility.
Bubblegum Crisis has a similar feel to Weiss Kreuz, in that it has a group of four female vigilantes trying to save the city from boomers, whereas Weiss is a group of four males saving the city from an evil corporate family. Of course, girls in skin tight power suits is never a bad thing either!
Mireille Bouqet has become a reputable assassin working in France. However, all changes after she meets Kirika, a mysterious young girl who knows nothing about her past but possesses killing skills that dwarf hers. Further intrigue unfolds as both characters explore their shadowy past and come to a head with a clandestine organization that seeks to control destiny itself.
In the underbelly of the corporate world, a secret series of battles takes place called the Bus Game, whose participants are solicited randomly via letters in the mail. During the games, teams of three attempt to take into their possession a disk filled with corporate secrets; the winners are given increasingly high cash rewards, while the losers get nothing - or worse, they lose their lives. Toki, Kazuo and Nobu make up the "no name" team, and their goal is to win one billion yen each. Each has a reason to need the money and a secret, disturbing past; but with high stakes and mysterious employers, they can only hope to leave the game alive.
I really wasn't a fan of Weiss Kreuz (the little I saw), and I'm not a huge fan of Bus Gamer either. Regardless, each of these anime has a very, very similar feel and character interactions. The stereotypical bishounen boys will seem like spitting images of each other, and in general the confusing mix of quirkyness and seriousness will seem similar to you.
Ban Midou and Ginji Amano are the Get Backers. With a 99 percent success rate in returning lost or stolen property to its original owners, they will do anything for the right price. Midou and Ginji often get hired for seemingly ordinary jobs that turn out to be more difficult than they appear; and whether it’s finding a doll for a girl, retrieving a stolen rare violin or getting mixed up with the mob, they have many adventures with plenty of petty squabbles along the way!
Like Weiss Kreuz, Get Backers is about a couple of guys trying to get back stolen things for people, only in Backers they live in a pizza parlor instead of a flower shop. Still yet, they must fight against mafia type families or groups with specialized weapons/powers.
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.
Weiss Kreuz and Gunslinger Girl tackle the assassin genre by focusing on the killers themselves. In both cases we have tragic pasts that force the characters to become killers and the moral consequences of this are experienced by a highly emotionally damaged cast. GG treats its subject manner in a more convincing and heart wrenching way while WK borders on angst fest with hints of cheesy moments thrown in but both have enough in common to warrant this recommendation.