Renet (IDW)

Renet Tilley is a Timestress, apprenticed to Lord Simultaneous and an ally of the TMNT.

IDW Comics
In the IDW comic series Renet has her debut in a special story, where she "invites" the Turtles to the interdimensional Battle Nexus tournament. In this version she is also Lord Simultaneous' pupil in magic, dimension travel, and apparently his successor in the Dimensional Council.

At the time in which she appears for the first time, the cruel Councilor Nieli hosted a series of merciless gladiator fights, which only he really liked. Renet was also against the games for personal motives, because one of the champions, the warrior Baltizar, had won her heart. For this reason, they brought the Turtles to the hub of the dimensions and helped the culmination of these events to instigate an uprising against Nieli, which meant that Nieli was banished and the games were transformed into a far more peaceful affair.