I recently watched Belladonna of Sadness (trailer here [18+]: https://youtu.be/2WkcLMapo_Y), a 70s adult anime that blew my mind. It was in watercolor and so beautiful, and full of psychedelic imagery. It brought my mind back around to one of my favorite anime styles, which is 70s shoujo. So I looked up some reference pictures of another 70s anime that’s more famous, Rose of Versailles, and drew Byleth in that style.
It’s not exact, but I had fun with it. Byleth liked it because he loves everything to do with the 60s and 70s. He’s also a pretty boy himself (or more accurately, a hot dad type with just enough muscle to make me swoon).