Sumomomo Momomo: Chijou Saikyou no Yome

Both very similar in every aspect. A lot of weird humour and the typical "strange girl who falls in love with a boy who doesn't really seem to cope with that love". 

Similarities: Both have a sudden girlfriend appearance genre. Both have comedy, harem, action and school genre. Both chiquitas (female lead) are the ones protecting the reluctant muchacho (male lead) Both have instances where the muchacho (male lead) is reluctant to get involved with the girl but seem to be stuck with the chiquita (female lead). Dissimilarities: One has an extra sci-fi genre while the other has martial arts as its extra genre. The girl in one anime is an alien and an otaku, while the other girl from another anime is a martial arts expert and good in doing household chores. The muchacho (male lead) in the other anime has a childhood friend who also is his secret protector, while the muchacho in the other anime has no childhood friend.  read more 

Both are forced relationships where Rizel and Momo are totally obesessed over their husbands, and the guy does not want them. Also, the constant tossing of fiances, and also, the overdose of females crawling over the protoganists. Not too mention adorable songs for both animes. 

The intensive world of martial arts versus life in the modern city is a major theme in both shows. There are characters in both who are from martial arts families but want to live a 'normal' life but are constantly pushed to train martial arts. There are lots of comedy, ecchi, fighting, and ninjas in both. Both protagonists find themselves surrounded by girls. 

Two energetic girls are present as the main protagonist in these two series. On the other hand, there's the main male protagonist who has a strange relationship with her. Throughout each episode, they show a deeper care for one another that borders on romance. There are also other girls with different personalities as well but all have a passion for fighting and the ninja arts in both series. Although neither series are any special or great, they do pass the time with their comedy, drama, action, and amusing scenes. 

In both shounen series, martial arts is a major theme that plays a dominant role in nearly episode. The main protagonist gets involved with oth er characters in the fields of martial arts. In both series, the main heroine is strong and relies on her martial arts skills to get by. Both series also contain comedy presented in humorous ways that also contain bits of drama later on as the episodes progresses. 

Funny shows about forced relationships, in Sumomomo Momomo the main girl often tries to seduce the main boy, while Nisekoi plays on characters' embarrassment. Nisekoi is more traditional school comedy, while Sumomomo Momomo gives action and fights. There are exactly three girls which love the boy. 

Both are about a smart guy who is protected by girls who know martial arts and both are harem-Ecchi-comedy-actions.Both male MCs are usually cold to the girls but the diffrences is that in Maji de Watashi ni koi shinasai! The male MC is a little perverted but try's to fight even though he cannot do much,while in Sumomomo momomo the main guy just avoids violence. 

the feeling they give are similar both mc have to deal with woman that make their life more interesting both story are kind of similar in the sense that both mc are stuck in a relationship with girls completely opposite of them both mc are serious type  

Supernatural-Harem setting,protagonist seems like a weakling at start but stood out later with a hidden power. 

Girls fighting over a guy who is not interested in them. The girls trying to seduce the male character. Sumomomo Momomo is focused on martial arts, while the other one is focused on brother complex. 

Both are about a powerless guy who is protected by superpowered girls,and both are Harem-Action-Ecchi.Differences are in Sekirei the girls are who's being targeted while in Sumomomo momomo it's the guy,also the Male main Charcthers are almost opposites,In Sekirei he is trying to protect the girls even though he can hardly do anything and attacks obstacles head on while in Sumomomo momomo the main guy hides behind the girls and try's to weasel himself out of everything. 

It's very similar in the sense of *cough* perv. But less so. It's an interesting anime like Club-to-death Angel Dokuro-chan, so i would recommend it. 

The only thing similar is the concept of the forced marriage aspect, and the growing love between the main characters 

Both series story revolves around Chinese Zodiac. 

Both evolve around the same pervertedness that involves the female character wanting to have sex with the male character. Same type of comedy used too. 

Basically in the beginning of both shows the protaginist was a bit of a wimp for his smarts and felt that people who bullied him were inferior to him.Then one day all that changes when they meet an unwanted partner who somehow gives them the courage and strength to fight back and learn what it means to stand up for yourself, and they slowly forge a bond with their partner that cannot be broken. Also both of them are pretty hilarious. :D 

Like Sumomomo, Ranma 1/2 incorporates martial arts families, an arranged marriage, love dodecahedrons, and lots of comedy. Ranma 1/2 has the additional twist of the water-induced sex-change problem. 

Girls fighting over a guy who is not interested in them. The girls trying to seduce the male character. Sumomomo Momomo is focused on martial arts, while the other one is focused on brother complex. 

The protagonist is a girl who has trained in martial arts with her father all her life. That's about it for similarities since it's also a slightly ecchi comedy with loli elements, but it's an okay pick for people who like anime with a powerful female fighter and can look past the perverted stuff. 

After many years, the male protagonist is reunited with his childhood friend, a small but extremely high-energy girl. He doesn't remember her very well or doesn't want to remember her because of all the crazy things she put him through. While the girl practically clings to him, all the boy wants to do is read books. There is a small level of romance between the two although the boy doesn't want to recognize it. Both are very funny shows. 

Pretty girls trying to seduce the male character. The target is an arranged marriage. The male character of Sumomomo Momomo rudely refuses and rejects all the girls, while the guy of NakaImo simply tries to resist to the seductions.