the sistem:

The people gets plush of their soulmates, and the person feels what its happening to the plush/doll, and the person who have a plush of him/her its their soulmate, and they need to find who have the plush/doll

ex: if u kiss the doll, he/she feels kiss his too;if u hurt the plush he'll/she'll get hurt too etc

Tanjirou feels like someone its hugging him and kissing him, while holding the plush of his soulmate

(you hug the plush and he feels this)