The Only Favourite Ugly Husband - Chapter 124.1 - School And Cooperation

Crossing into the world of Naruto, and acquiring the One Piece system, with all the powers of the world of One Piece, swordsmanship, devil fruit, domineering.

-Do you think that your fire is very powerful? I have the burning fruit.

-Do you think that your thunder is very powerful? I have a thundering fruit.

-Do you think that your otter is very powerful? I have the frozen fruit.

-Did you said you want to die? Don’t worry, I also have a nickname: Death Doctor.

- Description from Novelupdates

Igor had asked him to die for the world. She would ask him to die for her. Problem was, he didn't really like dying, not for a second time, at least.

Entering Tokyo in the bubble era, in this strange era, the only familiar ones are Matsuda Seiko, Nakamori Akina, Kudo Shizuka…

- Description from novelbuddy

She is intelligent, beautiful, calm, and professional. As the youngest chief forensic investigator for the past few years, her future was very bright. All of this, however, changed with a bizarre time-travel.