Legami Invisible Magic Ink Pen Unicorn

Invisible Magic Ink pen from Legami. How does it work? Well, thanks to its dual tip, you can write with normal blue ink. Nothing magic about that. But the other end is invisible ink, and it's only visible under UV light. Fortunately, the cap of the Invisible Magic Ink pen is equipped with such a thing, so you - and only you - can see what you've written.

Unicorn-themed. Because unicorns are magic!