Rosetta Stone is a character appearing in Professor Layton and the Unwound Future. She is one of Layton's students at Gressenheller University, and is very passionate about her studying. Her flirtatious behavior towards the professor seems to scare him quite a bit. Later on in the game Layton and Luke go back into the past and search out some clues and they meet her outside of the university.
She has a thing for Layton and is apparently in his class for the credits. She also wants a special study session with Layton as well. Her writing, according to Layton, wasn't that bad but could also be better. Rosetta then suggests that she studies more than Layton thinks. She is seen in the credits as well with Luke, Layton, and Flora at Gressenheller talking to her.