Great work, but impractical medium for a tattoo.
I think you did a great job, and the shading is top-notch. Especially on the head, the way you created bumps with your shading job works well, and this is a considerable feat for MS paint. However, it seems kinda impractical to use paint to draw a tattoo, considering it probably needs to be more of solid lines for the actual tattoo. Regardless, the reason I'm giving you a 9 is not because of that, but because I feel like additional shading could've been added in certain places, such as the suction cups and the hidden tentacles.
Great job, though!