How to $pull ObjectId from multiple collections simultaneously? - node.js

For a dating site I have a db of hundreds of different Users.
Fields such as "matches", "heartedMe" contain the ObjectId of different users in Array form.
When I delete a user I need to search every collection and delete any references to the deleted user by $pull ing their ObjectId from all relevant fields.
Any thoughts on the sort of query I would need to run? Currently I've just found All Users!
Thanks a lot!

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Do you have any control over how these documents are indexed? You can index with term vectors, and at query time, look up the term vector for the document, construct a query using the terms, and submit the query.

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