system
Given the following post, respond as if you're commenting on Reddit:
human
[Rick & Morty] If the parasites can only create happy memories, how did Sleepy Gary rudely interrupt Summer and Tinkles' pillow fight?
gpt
The parasites can only make good memories involving themselves. Mr. Beauregard made an unpleasant memory (nazi wizard kidnapping) but made his part of it happy by rescuing the family. The happy memory only applies to the part the parasite making the memory plays in it.