My Bride is a Mermaid - Recommendations

Alt title: Seto no Hanayome

If you're looking for manga similar to My Bride is a Mermaid, you might like these titles.

Raise wa Tanin ga Ii

Raise wa Tanin ga Ii

Follows Yoshino, a mafia boss' granddaughter, whose pedigree has left her without a boyfriend because everyone is terrified of her. Her love life takes a different turn when her grandfather sets her up with the grandson of another mafia boss named Kirishima. Yoshino goes to live with him, but his kind and intelligent demeanor hides a dark side. 

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Sore wa Totsuzen, Unmei no Aite ga

Sore wa Totsuzen, Unmei no Aite ga

Imagine a country where couples are chosen based on the compatibility of their genes. Whenever a resident reaches the age of 14, a partner will be suggested to him or her based on which match would result in the best child being born.

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Shiritsu Kiwamemichi Koukou

Shiritsu Kiwamemichi Koukou

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Maji!

Maji!

Experience the life of a young member of the Japanese mafia. Our main character, Maji, lives his daily life as part of the Nagisa-gumi, protecting the locals and running their turf. He may not be the smartest man in the world, but he has the guts and attitude to become a great Japanese mafia member.

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W Change!!

W Change!!

High-school student Kisaragi Maki has one dream: to be a normal wife. She’s part of a Yakuza family known as Group Kisaragi and her father is the third generation of the group - and he wants Maki to be the fourth generation! But Maki isn’t a ‘normal high school student’. She has a split personality which gets her into all sorts of trouble. Can Maki achieve her dream of being a ‘normal wife’?

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Jingi Naki Mukotori

Jingi Naki Mukotori

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Koi to Dangan

Koi to Dangan

Yuri, a college student, is saved by Ouya Toshiomi, the young leader of the Ouya group when she’s being forced into consuming illegal drugs at a party. Since then, even though she doesn’t want to get involved with the internal dealings of the Yakuza, she can’t help but fall for Toshiomi’s surprisingly gentle smile. This is the story of two people who are attracted to each other, but the courtship of a man who lives staking his life may be too fierce and crazy…

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Shikanoko Nokonoko Koshitantan

Shikanoko Nokonoko Koshitantan

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Adeotoko Shichihenge

Adeotoko Shichihenge

Misono has a secret... she's a yakuza's daughter! In order to cover up her background, she has attended a famous private school with her seemingly "plain" assistant/boyfriend Yuuki. Although they are lovers, things are going nowhere in their relationship, how can Misono take the relationship to the next level when her boyfriend acts too much like a servant?

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Chouka-han ka: Gokudou-sama Afurete Afurete Naka Setai

Chouka-han ka: Gokudou-sama Afurete Afurete Naka Setai

A JK young mistress x the leader of a yakuza group!? A dangerous love that is unheard of by previous generations!!! The Young mistress Miumi got abducted to the world of the yakuzas!? There, she met the young leader Mikogami…… Unpredictable!! Excitement at its max!! The too dangerous love is beginning—!!

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