Blame is a tricky, tricky thing. He'd like to displace it, faulting circumstances outside his control.
Emotional states, however, are well within his careful control. His son's sudden arrival, coupled with the news that one of his closest friends would be arriving shortly, left him with little room to think about birthdays.
He'd make it up with fleeting remorse if it were anyone else's. Of all the birthdays to forget, it had to be Mitama's. Their interactions leading up to now have been cordial at best, even if he did burn her during their winter vacation.
It's more than that, now. Siegbert loves her; therefore, Leo needs to make an effort to develop some kind of friendship with the poet.
Step one towards the goal is not off to a great start.
He's only one day late. Things could have been much worse. Prince finds Mitama on the monastery grounds. He adjusts the box in his hands, calling out in greeting. "Afternoon, Mitama. A belated gift. Accept my deepest apologies."
Inside, she'll find a leather tome containing various mythos from around the known realms. Another, smaller volume sits underneath: collected haikus from the greatest Hoshidan writers. He's sure she's already read at least half of them, but he's also ashamed to admit he doesn't know much of her likes and dislikes.
The day passed with Siegbert her sole source of fanfare and, in all honest, Mitama preferred it that was. She hardly expected anyone else to stride along and give her well-wishes simply for failing to perish. She knew it inevitable with Siegbert, but she could not think of anyone else who would think to celebrate the day.
That is why, when Prince Leo finds her the next day and hands her a gift, Mitama openly stares at the presented object for a beat too longer than what she could have simply dismissed.
She is...surprised. Genuinely. She takes the box from him, examining it with wide eyes silently as she turns it. A trick? A jest? She does not see one, though she still finds it hard to believe...
"I..." She clears her throat and closes her eyes briefly before meeting the prince's gaze. "Thank you. Pardon me, I do not wish to seem rude or unappreciative for the act, I simply..."
Now how does one explain that they are used to the day barely being of note, even if her father did remember it, and how does she avoid sounding utterly pathetic when she does?
"I was...under the impression that birthdays are not a particularly celebrated event." No, still not good. She suppresses the wince she wants to give herself and bows politely instead.
"Thank you, truly. I am quite grateful for the gift."