There is probably some slick multi-sig solution, but how do you think it would happen? idea just to kick it off ...

0. Establish an Anonstrich user (could even throw away the the private key)
1. Nostr1 Creates a message to Nostr2 and encrypts it with Nostr2's public key.
2. Nostr1 sends public message to Anonstrich (contains encrypted message for Nostr2)
2. Nostr2 scans all of AnonyStrich public messages and can only read the ones encrypted with their public key.