Bear in mind these are crude ideas at the moment.
Robert and Sally Rochester, twins with opposite peculiarities.
Name: Robert Rochester
Gender: Male.
Pronouns: He/Him
Physical Age: Constantly changing, but every reset puts him in his early 20s.
Real age: Over 1,000 (his time) or 60 (normal time).
Peculiarity: His personal time runs faster, effectively giving him super speed (due to speed being distance divided by time and the massive difference between his personal time and normal time) but at the cost of being forever loop-bound.
Notes: Loops are the only reason he's lived 60 years (normal time): the daily reset rewinds one's biological clock to the last physical age one was when one entered the loop. When it's his turn to leave the loop to keep it stable, he grabs a stick and sticks it through the loop entrance and pulls it back in. When he leaves the loop, it's always with Thomas Stopper.
Name: Sally Rochester
Gender: Female.
Pronouns: She/Her
Physical Age: 11
Real age: If it's based on her perception of time, she's 12. If it's based on normal time, she's 60.
Peculiarity: Her personal time runs slower.
Notes: While she's more resistant to aging forward, being in slow motion means she cannot leave the loop alone. If it's her turn to leave to keep the loop stable, someone else goes with her to the loop entrance and stays on the looped side.
I came up with those 2 ideas separately but realized how ironic it would be if they were twins.
Name: [Placeholder1]
Gender: Female.
Pronouns: She/Her
Physical Age: 3
Real age: 70.
Peculiarity: Ages in reverse.
Notes: Manifested on her 13th birthday. She was running around for 10 years before an ymbryne found her. She desperately wants to regain those 10 years (everyone else treats her like a baby) and has a plan to slowly regain them with Thomas Stopper's help. Anytime she leaves the loop, she does so with him. If she begins aging forward, Thomas's gift could stabilize her without a loop.
Feel free to suggest a name that means "reverse".
Name: Thomas Stopper
Gender: Male.
Pronouns: He/Him
Physical Age: 9
Real age: 40.
Peculiarity: When other peculiars are within a certain radius of him, their peculiarities don't work.
Notes: Very useful for keeping order at mealtimes.
Name: Howard Glass
Gender: Male.
Pronouns: He/Him
Physical Age: Early 20s
Real age: 900, owing to some encounters with Robert Rochester.
Peculiarity: Mimics peculiarities within a certain range of himself..
Notes: Due to not having peculiarities (other than his own) full-time, he tends to notice side effects of them, like glaciators having a slightly lower body heat than normal and sparks having a slightly higher body heat than normal, meaning he is of tremendous assistance when it comes to categorizing peculiarities. Tends to try to avoid peculiars with morphological peculiarities, particularly those with backmouths. He doesn't mind being near invisibles, though, as his form is the same.
Name: Miss Emu
Gender: Female.
Pronouns: She/Her
Physical Age: 70
Real age: 500.
Peculiarity: Turning into an emu and looping time.
Notes: A highly unorthodox ymbryne who delights in taking care of children with rather unusual peculiarities and is partly in charge of categorizing peculiarities.