It's Just a String『ただのひも 』

Back when they were Genin, Team 7 had a mission that needs to escort a Pregnant woman who bares a child that probably will have a special visual prowess.
"Really Mei-san? your husband's clan have that power to see who is your Soulmate?" the Pink haired girl in their teammate said showing much of her amazement. "-But not exactly sees them, they can see a red string attached to a person and the end of string is attached to your soulmate." the pregnant woman smiles at her.

"Woah! That's amazing!"
Naruto said enthusiastically.

"It is. If I had the chance I would like to know whom am I destined to be with." She glance over her teammate who's showing no interest on the conversation the two females are talking about.

When the time has come Sasuke knew who exactly it was. He said it was Ridiculous.

It's just a string after all.