When Michael Ausiello of TVLine was asked if Vanessa Lengies' Sugar would be appearing in Glee's 100th episode (season 5 episode 12, "100") - due to her show Mixology wrapping for the season - the answer (as of now) is....
Question: With ABC’s Mixology now wrapped for the season and with New Directions short a few members, is there any chance of getting a little Sugar in Glee‘s 100th episode? —Matt
Ausiello: Vanessa Lengies hasn’t been approached so, as of now, it’s going to be Sugar-free.
Aw, you mean we're not going to be getting some Sugar anytime soon on Glee? What do you think, would you like to see more of Vanessa Lengies on the show?