Hadiya's Handy Quill
This dart doubles as a magical quill and is fletched with three iridescent crow feathers. Immediately after you make a ranged attack with this magic weapon, it flies back to your hand. When you make a ranged attack with the dart, you can speak its first command word as part of the attack to cause the dart to release a splatter of ink. If the attack hits, the target is blind until the end of its next turn. A creature can use its action to clear away the ink on itself or another creature within its reach, allowing it to see again. This property can't be used again until the next dawn.
When used as a quill, the dart produces its own ink unless you provide it with a different one. You can choose what color ink the quill produces by speaking its second command word as a bonus action.
In addition, you can use a bonus action to speak the quill's third command word to cause it to vanish and reappear as a feather-like tattoo on your body. You choose the design and placement of the tattoo each time. You can use a bonus action to speak the command word again while you have the tattoo to cause it to vanish and reappear as a dart in a free hand or at your feet (your choice).
The Librarian was an avid note-taker and strict enforcer of rules. Step out of line, and you ran the risk of losing more than simple reading privileges.