Complex sentence: After this, Amy and Bender discover a mutual attraction for each other and enter into a robosexual relationship, which is taboo in the 31 st century, so they keep quiet about their relationship, even to their friends and co-workers.
Split into simpler sentences: After this, Amy and Bender discover a mutual attraction for each other and enter into a "robosexual" relationship, which is taboo in the 31 st century. Because it is frowned upon, they keep quiet about their relationship, even to their friends and co-workers.