blocking on this site:

You can block any account on the site — registered users, guests, or chatroom visitors — and guests can also block others. There is now a single block system that works uniformly across all account types. Blocks happen instantly and stay in place until you remove them.

effects of blocking someone:

When you block another account:

• the blocked account will not be able to see your profile page anymore
• the blocked account will not be able to see your pictures anymore
• the blocked account will not be able to see your favorites anymore
• the blocked account will not be able to send you instant messages anymore
• the blocked account will not be able to start a video call with you (the call is dropped server-side, you get no ring and no notification)
• the blocked account will not see you in the search results anymore
• you will not see the blocked account in the search results anymore
• the blocked account will appear in your list of blocked users or list of blocked guests (depending on the account type) and you can go there to unblock the account at any time

extra layer for guest accounts:

When you block a guest account, we also remember the IP address that guest was using at the time of the block. If the same person discards their guest identity and creates a fresh one from the same IP address, that new guest is still blocked. This is to prevent the trivial “reload to get a new identity” bypass that guest accounts otherwise allow. It does not apply to registered users (their identity already persists across IP changes) or to other transient account types.

how long blocks last:

Blocks are kept indefinitely. Once you block someone, the block remains in effect until you remove it from your blocked list. The only exception is virtual users (a temporary identity used briefly before registration or account choice) — blocks pointing at those expire after 30 days, since the virtual identity itself is gone by then.