Sonny

Sonny stands a mere 4 meters, tiny by the standards of its kind. A mop of messy blond hair sits above pale blue eyes, its skin carries the light peach tone typical of ordinary Titans, and a dazed, vacant expression rarely leaves its face.

Nothing separates Sonny from the mindless majority of Titans. Its intelligence is minimal and pain barely registers; when researchers drive a spear through its heart, the wound goes ignored entirely because Hange has strayed within biting range. Deprived of sunlight, it slumps into near-total inactivity within a single hour, far sooner than its fellow prisoner Bean. Hange sums up its disposition by calling the creature introverted.

Sonny enters Trost District among the horde that pours through the gate destroyed by the Colossus Titan. After Eren Yeager plugs the breach and human forces reclaim the district, nearly every Titan trapped inside is slaughtered, but two are kept alive for study. Hange nicknames the pair Sonny and Bean, a combination referencing the infamous cannibal Sawney Bean, and subjects them to trials testing communication, reaction to injury, and sunlight deprivation.

Further experiments are planned, but during the night both specimens are cut down by assailants nobody can identify. Armin Arlert eventually reasons that Annie Leonhart carried out the killings, evading suspicion during the investigation by using vertical maneuvering equipment taken from Marco Bott. Years later, in 854, Reiner Braun remembers that destroying the captured Titans was originally his idea rather than Annie's.