Sr. Tachibana is an elderly man who, with his wife, finds Lalabel unconscious and shelters her in their home. He initially displays cynicism toward magic and remains skeptical of Lalabel's abilities. His viewpoint transforms when she uses her magic to save him from nearly drowning, fostering acceptance of her powers.

He shapes Lalabel's daily reflections by creating original proverbs that she documents in her diary. These sayings connect to her experiences and deepening insights into human life. Sr. Tachibana offers wisdom and stability within the household, guiding Lalabel's observations about human nature and daily struggles.

His background places him within a multigenerational family, as his granddaughter Teko lives with the couple while her parents work abroad. This caregiving role naturally extends to his guardianship of Lalabel during her time in the human world.