Sergeant Winston Asher is a FEDRA soldier who once kept a camp and a horse in Boston's Liberty Gardens mall. In Left Behind, Ellie and Riley find his empty camp in Mallrats, and his notes show how he saw the two girls.
In Mallrats, the note is on a table in the room beside the circuit breakers. Winston asks Banks for more patrols for the third time in three weeks, because refugees from the collapsing Hartford QZ are pouring through the mall and many are infected. He says he killed three stage ones last week, then gives up mid-sentence, sure Banks will not listen.
In Fun and Games, the note is on the kitchen counter of the mall restaurant. Winston admits he came back early from patrol, found Ellie crying beside his tent while petting his horse, and slipped away rather than face her. Ellie finds reading it embarrassing.
Ellie and Riley look through his gear, Ellie spots the young photo and says he was handsome, and Riley finds his whiskey. Ellie can take a swig or pass.
Riley tells Ellie that Winston died of a heart attack, a strangely ordinary death in this world. The military took Princess afterward.
Ellie Williams
Ellie Williams is the 14-year-old girl Joel is hired to smuggle out of Boston, and your companion for most of The Last of Us Part I. She was bitten weeks earlier and never turned, so the Fireflies believe her immunity could lead to a vaccine. You play as her in the winter chapter and in the Left Behind DLC.
Riley Abel
Riley Abel is Ellie's best friend from the military school in the Boston quarantine zone and the co-star of the Left Behind DLC. She appears in the Liberty Gardens flashback chapters Mallrats, Fun and Games and Escape from Liberty Gardens, and Ellie brings her up during the main story.
Corporal "Dickhead"
Corporal "Dickhead" is the nickname Ellie and Riley give a FEDRA officer at the Boston military boarding school. He is only talked about in Left Behind, as the man who took their water guns away.
Joel Miller
Joel Miller is the man you play for almost all of The Last of Us Part I. A hardened smuggler in the Boston quarantine zone, he takes a job escorting 14-year-old Ellie out of the city, and the drop-off turns into a year-long trip across the country to find the Fireflies.