After I block someone on Facebook, can I see anything about that person?

Yes. Blocking allows you to prevent many interactions with someone on Facebook, but you may still encounter content they’ve shared.

Here’s what you might see:

Messages: Your message history with someone you’ve blocked will stay in your inbox. If the blocked person is ever included in a conversation with a group of friends, you may be able to see the messages. Remember, you can leave a conversation that you don’t want to be part of, or delete a conversation that you don’t like.
Mutual friend stories: There’s a chance that you'll see stories about the blocked person through mutual friends. For example, if the blocked person tags a mutual friend in a photo, you might see this story on your friend’s timeline.
Photos: You might see photos or tags of the blocked person added by other people.
Groups: Someone you’ve blocked won’t be able to add you to a group, but you’ll be able to see groups that the blocked person created or is a member of.
Events: Someone you’ve blocked won’t be able to invite you to an event, but you’ll be able to see events to which both you and the blocked person are invited.
Games and apps: Since games and apps are run by outside developers, the Facebook block won't apply to them. So you could see someone you blocked while you're playing a game (ex: in the game's chat room).