I've got two in mind. Firstly, I'm hoping to find something with a Mario Brothers formula, like Shin Mizukami's Rikara; A prince or king is abducted by an enemy prince or king & needs to be rescued. Or maybe their love is consensual, but their nations are at war with eachother. Bonus point if it's in a historical or fantasy setting. Double bonus points for long hair.

Secondly, I'm trying to retrace one I read years ago. It takes place in the 1700s or 1800s where a Japanese man is sold out by a fellow countryman to caucasian guys on a ship. He's abducted & delivered in a sack, & the whole crew is mollesting him when the captain claims him for himself. I also remember he was forced to dress like a geisha at one point. I'm certain it was a one shot manga.

Let's revisit the topic of long hair. If you can't help with the above two, perhaps you've encountered bl or yaoi where the seme & uke both have very long hair, as in at least below shoulder length. The longer the better.

Is the kidnapping manga Hagakure no Koi chapter 3?

Yes. ::hugs::