This command removes the perk with the specified ID from your target. Use the command 'player.removeperk' to remove a perk from your own character.
removeperk [perk id] Target Command
|Perk ID||The ID of the perk you wish to remove from your target.|
Atronach has a perk ID of 000581F7. This command would remove the Atronach perk from your current target.
This console command is very similar to the first example, but instead of removing the perk from your target, the perk is removed from your character (as 'player.removeperk' is used).