Ok, Some background info so that this makes a tiny bit more sense, even though this is just a quick Valentines story;
-500 years previous the mystics were reintegrated back into human society
-Right after that, WWIII occurred. It was 5 races against each other; demon vs angel; dragon vs hunter; and human bouncing sides all over the place.
And some info on Isao and Shan;
-Isao Masa is a dragon and the top general in the mystic army. He also personally trained Kiden, Hitaru, and their children. After the war, there was a time of peace, giving Isao not too much to do. Since all his previous students were all trained, he decided to start teaching PE in a public school. He is about 17,000 years old. He only looks about 22 to 25 years old.
-Shan Kagerou is one of Isao's students. She is also a dragon, and about a 30th Isao's age. She's around 500 years old. She looks 15 to 16 years old. Since she is sexually mature, it's about the same in demon society as reaching age 18 for humans.
Isao arrived at school shortly before the students. He sat down in his office and waited for the students filter in and change for their PE class.
When the bell rang, Isao went out to the gym. The boys were warming up for the day, while the girls stood huddled together, talking excitedly. Isao saw that they were all holding small red or pink packages that smelled of chocolate. He mentally groaned to himself. He never looked forward to Valentines Day, because all of his female students all tried to win his heart.
A few days before Valentines Day, Shan sat in her family's kitchen. She was debating on whether to take up the Challenge that was presented to her several months before.
She'd run into Masa-sensei during Obon, and through him had met the twin emperors and their mates. Mumei-sama had talked with her, and seemed convinced that Masa-sensei had some feelings for her, and challenged her to give him something for Valentines Day, and see how he reacted.
She looked at the ingredience for making chocolate and frowned. What is Masa-sensei didn't like chocolate? She didn't want to give him something he didn't want. She looked over at the phone and frowned more. What if her small gift would be covered up by all the other gifts Masa-sensei would receive. That wouldn't be fair odds for Mumei-sama's challenge. Since Mumei-sama challenged her, surely she'd be willing to help, right? It was worth a try. Shan picked up the phone and dialed Mumei's number.
At the end of the day, Isao looked into his office and sighed. He wasn't interested in keeping all of the chocolate he was given. All of his female students had given him something, and a few had snuck another gift into his office, then there were the females who weren't even his students as well. He was a pretty kind teacher and didn't want to be rude about throwing everything away, so he waited until most of the students at least had gone home before throwing everything in the back dumpster.
When he got back to his quarters in the palace, he went straight to his bedroom, hoping for a nap. He looked down at his mat, and on his pillow was a white box with a red ribbon and a small card. He took the card first and read it. It was simple, just a "Hope you like it. – Kagerou, Shan."
He smiled and opened the box to a very nice surprise. Kagerou must have had help, since he was presented with his favorite dessert.
He placed the card on his desk in his office, and then he took the box to his dinning table and ate a nice white cake with chocolate frosting, with some strawberries and raspberries.