lushp said:
A flexible thread is her weapon.

The tag is meant to be used for actual weapons. A random object used as a weapon is not an actual weapon. For example, a pencil or an umbrella can be used as weapons, but they are not actual weapons, so we should not tag a post with weapon even if the character uses those objects as such. Unless the object is specially (visibly, for the purposes of tagging on Yande.re) modified to become one.