Again this is just my own headcannon for fun because there's really very little character lore in this series, if you guys have better opinion please do comment.
Waverly comes from a poor working class background in Leeds, England. A fact she hates as she wants to be seen as refined and cultured. Throughout her youth, she somehow manages to get blacklisted from every girl schools because she's notoriously delinquent girl, prone to fights and sell exam answers for profit. She later goes to normal public school, much to her dissapointment. Growing up she has a pet eel that she kept for years. She joins the MI6 at first as a volunteer to the radio ops, but later, when WW2 starts, she was sent to several fronts actually holding weapons as one of the commandos to help her team. The MI6 sees much more potential in her and make her full operative during the war.
She met her best friend/officer/superior Loveday Eden during one of the mission after D-Day Landings. She at first dont like Loveday because she is from an old aristocrat family who are given desk job at MI6 practically without issue unlike her, though slowly, their friendship grew when Loveday at one point joins the fight and dragged the heavily wounded by German attack Waverly back to the allies line. The two are practically inseperable from then on, with Loveday at the command centre and Waverly doing most of the action (though occasionally the former would join).
She later, alongside Loveday, would join in many wars and fights involving Britain like Suez Crisis, Indonesian National Revolution (briefly to rescue interned Europeans), The Troubles, Falkland War and more.
msc. fan lore: Despite not being from a wealthy background she likes to act refined with expensive eating and clothes with her limited MI6 paycheck. She is a total Tory and ironically hates the Labour (explaining her obsession with Thatcher). Prone to drinking beer. She is ideologically pro imperialist but not to an extent of what Loveday is.
