Fire Emblem: Ultimatum (A Visual Novel series!)
ldn09 for Dedue
Dedue is a supporting character of Fire Emblem: Ultimatum and a member of the Blue Lions house. He is Dimitri's sword and shield, and has offered his life up to serve the prince in whatever way is needed. He is typically stoic and direct in his interactions with others.
Voice reference: https://www.youtube.com/watch?v=3iomvAiSUZA
"Please, your Highness, allow me to accompany you to the tower. There is no telling what the Emperor has planned, I am worried."
"Thank you for your teachings, Professor. You manage to describe battle tactics better than the other professors do, it's...appreciated. Would you mind if I asked for a review for the next textbook?"
"His Highness is the top priority. If you continue to spend time with me, you will only be disappointed in what you find."