"Kiva" can refer to a number of characters, artists, and other things. Check the current list of kiva* tags to see if there is a more specific one that fits what you are trying to tag.

Some of the more popular tags from the list include...

Artists

• kiva
• kivalewds

Characters

• kiva_(amazon)
• kiva_(partran)
• kiva_(kiva)
• kiva_(utopianvee)
• kiva_(tsaiwolf)

...but check the complete list if the one you want isn't listed here.