As we all know Yuichiro's based off of Jadeite. The staff liked the idea of Rei having a love interest who moves in with her after her debut episode with Jadeite. Notice how Jadeite had hair that covers his face in her debut and only her debut just like Yuichiro.
Speaking of which, I can't believe they revealed that Yuichiro had to grow out his hair, so the police don't recognize his face. He used to sell these weight gain bars. That part of his past manifested from an unused plot where Jadeite sold weight gain bars as an adaptation of the Sailor V plot where a that happens. DiC included a nudge this detail although it was never mentioned in the Japanese version
None of the people who ate them were able to catch him from all the weight they gained though... that explains why he works at a shrine to "better himself" as well. It all makes so much sense now.






Speaking of which, I can't believe they revealed that Yuichiro had to grow out his hair, so the police don't recognize his face. He used to sell these weight gain bars. That part of his past manifested from an unused plot where Jadeite sold weight gain bars as an adaptation of the Sailor V plot where a that happens. DiC included a nudge this detail although it was never mentioned in the Japanese version
None of the people who ate them were able to catch him from all the weight they gained though... that explains why he works at a shrine to "better himself" as well. It all makes so much sense now.