Tatsunoko's Pixiv Collection - Ch. 1 - The story of Brothers That Yearned To be Detective and Phantom Thief

[MangaDex]

 

[EarlofMillenium]

They swapped but are no doubt both terrible spouses.

 

[KatoShuu]

but there's still one question, what's his Kaito name?

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Fanbox chapter

 

[IrregularPerson]

their acting as each others favorite character to get into each others pants- if it wasn't for that brother comment. lol.
Kaito means "mysterious" so it's alias isn't it?

 

[Stadenwick]

Well they're siblings alright

 

[laiseran]

The plot twist

 

[A_Crappy_Connoisseurs]

Yup, siblings

Can be a gift or a pain.