A miniature Beggar.
A following Beggar Familiar that seeks out and picks up coins for himself to use when Isaac is not in battle. After getting random amount of coins, he returns to Isaac and drops a pickup, which may include Hearts, Coins, Bombs, Keys, Tarot Cards, Pills or Trinkets. If he gets a dime or nickel, it will be counted as getting multiple coins in a row, so there is a chance for him to drop multiple pickups.
The Bum Friend has a slightly higher drop chance than a Beggar, and is capable of dropping Trinkets, which a Beggar cannot. However, the Bum Friend will never drop Collectibles.
The Bum Friend is capable of flight, and can reach coins which are unable to be reached by Isaac due to rocks or pits surrounding them.
Be wary of drops from Bum Friend, as he may occasionally drop Troll Bombs as well as the Tick Trinket, which can potentially make it impossible to reach The Chest. Standing too close to the Bum Friend when he is spawning loot may cause you to unintentionally pick up items you may not want. Additionally, he can push around Isaac's placed bombs, causing them to be wasted or deal damage to Isaac.
- IV Bag - Allows the Bum Friend to easily get more coins, although this will make it difficult for the player to get the coins for themselves.
- This also applies to the Blood Donation Machine and other coin-generating objects. Combined with IV Bag's infinite money bug, Isaac can get infinite pick-ups.
- Reverts Little Steve, Robo-Baby, Rainbow Baby, and Little Gish to Brother Bobby.
- Getting Brother Bobby will change your familiar back to its normal form.
- Due to Bum Friend only picking up items when Isaac is not fighting, if coins are obtained from a chest in a challenge room and the enemies spawn just as Bum Friend is getting ready to spawn an item from said coins, the game will freeze.
- Rerolling Coins with the D20 while Bum Friend is moving to pick up a coin will make Bum Friend disappear completely for the current room.