Wait a minute if elves take a hundred years to grow up that has some weird implications.
So… if we say a human comes of age in fantasy worlds at 16, that means it takes an elf 6.25 years to age one human year. If we say the age of maturity is 18 that’s 5.55 years.
So then… okay with people that live a long time have to see their human friends die and probably see them like pets yeah that’s been explored to death. But what about a human just seeing their friend not grow up?
An elf toddler and a human toddler become friends at a playdate. At the time the human is two and the elf is 13. Emotionally the elf is just a little older than the human. But then the human grows up. He grows up and as he grows up his friend doesn’t. Not much, anyways.
She’s still sucking her thumb and throwing tantrums the entire time that he grows up. When he reaches the age where he’d choose a trade or go to an academy he’s earning extra money by babysitting her. During his initiation into adulthood on his 18th birthday she’s there with her parents holding a stuffed animal. Later that afternoon he sees her being shown some colorful flashcards with letters of the elvish alphabet on it by her father.
The human gets older. He learns how to fight, he goes from town to town getting work. At some point he joins the army. Every time he visits his hometown he has at least one more scar and by the time he’s 30 and the elf girl is mentally seven by human standards she starts to understand that something is wrong. Even after he settles down to be a home maker for the local blacksmith something feels wrong.
And she watches him grow old. When she’s in her 80s she babysits his grandchildren for extra cash after school, coming over in her school robes and ruffling his hair. She doesn’t remember why she became friends with this human or when but a strange sense of jealousy fills her heart.
Now she realizes it. She realizes it too late, on the day her friend learns that he is dying. The first day of her 100th year and the start of his last. Humans’ lifetimes may only last for the childhood of an elf if they’re lucky, but they learn so fast. They do so much. They cram their days full of love and hate and learning and wonder.
He knew this was coming. He knew all of this decades before she did, because elves are slow. Not stupid, certainly not stupid, but very very slow. She holds her old friend’s hand as he lays down on his bed. A man that has led such an ordinary life but feels so extraordinary to her. Because he has always, always been there and now he just won’t. Because in her eyes he became so wise so fast and now he’s just gonna be gone.
On an elf’s 100th birthday they are allowed to choose a new name for themselves. It can be important, or not. Usually it will follow them until the end of time. She stands in front of her family’s elders and is asked what name she will be called from now on.
She names herself after him.