Sekai de Ichiban Tsuyoku Naritai!

Girls humping each other. 

Both are wrestling themed anime and involve a MC who got his butt kick by a bad ass wrestler before getting into the sport. Both MCs have guts to even think about getting into such sport. The MC from one anime is a girl whose honor was ruined by a cocky female wrestler, while the MC in the other anime is a lazy and rowdy tough guy who got owned when he insulted a group of sumo wrestlers. One is based on a WWE diva theme, while the other is more into the traditional Japanese sumo wrestling. 

Both anime have similar have similar sports genre, pertaining to contact sports, except one more into boxing where the guy has to defend his belt, while the other is into all female wrestling where the idol has to defend her honor.  

Do you want more female wrestling? A quite hard to find theme in Anime. Girls getting beaten up in the ring until they improve their fighting skills is pretty much the common theme of both series.  

Cute girls in skimpy outfits doing wrestling. 

Both titles take place in the world of wrestling. They include a lot of action in the ring, masked fighters, and wrestling techniques. The common theme is "becoming stronger". Differences: - Sakura Hagiwara loses most of her fights, while Tiger Mask (Naoko Date) usually wins. - Sekai de Ichiban Tsuyoku Naritai features more boobs, while Tiger Mask features more brutality. 

Both anime about wrestlers and wrestling. Both anime about the guys who want to become the strongest wrestlers. The young guys of both anime challenge the best wrestler of promotion. In the course of a career they meet strong rivals and tested for dangerous techniques currently. The guys of both anime expect startling twists in their careers. 

+ A story about a woman who dreams of becoming a professional player + She must build reputation from ground with alot exercise and pain + Theme "My Fren is My Enemy" can be found in both anime (Himuro Izumi & Miyazawa Elena) 

Our main heroine vows to beat the strongest wrestler in the world. One series takes place in the future while other does not. Sakura is an idol singer while Miku is a normal girl who loves wrestling. Sekai de Ichiban Tsuyoku Naritai has fan service + idols + wrestling while Metal Fighter Miku has no fan service. Both series depict the art of wrestling.  

all I have to say: if you don't live alone in your house make sure you wear headphones or you'll have some explanation to make. And make sure nobody is watching 

Both shows feature the common elements of females brawling with each other in skimpy outfits. Both shows actually have a bit of redeeming value in their messages on top of their primary draws of females in skimpy outfits brawling with each other. If you're picked up this show because it featured anime girls fighting with each other you should check out Zettai Shougeki, it's more brutal than SekaiTsuyo but it's also more over the top. 

I just have to say Hajime no Ippo is an amazing anime and Sekai de Ichiban Tsuyoku Naritai can qualify as a hentai. Lets just call it SITN for now. I thought they are sort of similar after finishing SITN's first episode. They're both about doing these fighting sports where nobody could ever think this person would have the strength or the guts to do. They each have a goal and each work themselves up from people telling them they can't do. Someday, though, they will do it.