Believing they are attempting to use Rick's ship to power a superweapon that will spread them to Earth, the duo manage to fight their way off the Glorzo home asteroid, causing mass destruction along the way.
Summer explains that after Rick and Morty fell under the control of the Glorzo, she was spared due to a toothpick in her mouth, which prevented the parasites latching on to her face.
She convinced the Glorzo to reform their society, abstaining from their usual practice of constant reproduction (a process that kills both them and their host bodies, which burst open as they lay new eggs).
In the post-credits scene, Summer's friend Tricia Lange notices Jerry's new beekeeping hobby, expressing more and more intrigue until she admits she's sexually attracted to him.
[3] According to Nielsen Media Research, "Promortyus" was seen by 1.34 million household viewers in the United States and received a 0.74 rating among the 18–49 adult demographic.