Spencer Hastings

In the TV series
Spencer's newly-engaged and condescending sister Melissa moves into the guest house which Spencer had been fixing up for herself. Spencer finds herself increasingly attracted to her sister's fiancé Wren Kim, whom "A" warns Spencer not to kiss or "A" will tell. Spencer and Wren do kiss and are caught by Melissa, who insists that Wren move out. Spencer starts dating a worker at the country club to which her family belongs, and later hides from her friends the news that her mother has breast cancer.

In the books
In the books Spencer is an incredibly smart, but an extremely competitive student, who is Alison DiLaurentis' both rival and friend. Spencer has a older sister, Melissa, who returns home from college with her fiancé, Wren Kim, who Spencer is immediately attracted to, Spencer and Wren almost have sex in the Hasting's barn, which is temporarily Spencer's room, this leads to Melissa and Wren breaking off the engagement. She does have a brief but intense relationship with Wren even losing her virginity to him. For a homework assignment for Economics, Spencer steals Melissa's old homework paper which her teacher ends up placing it into a nation-wide competition, and is eventually nominated for a Golden Orchid; she eventually wins the Golden Orchid, which she feels guilty for. Spencer keeps having a flashback of her pushing Ali to the ground the night of her disappearance and comes to believe that she killed Alison herself. Her sister reassures Spencer that she isn't the kind of person to kill someone, which then leads Spencer to believe that Melissa killed Alison. Later on she discovers that her father had an affair with Alison, Courtney and Jason's mother, Jessica DiLaurentis and Alison and Courtney are her half-siblings. She begins to fall for her rival Andrew, and they become boyfriend and girlfriend.

Relationships
In the Books Spencer has a relationship with the following:
 * Ian Thomas: They kiss and he flirts with her.
 * Wren Kim: They become a couple for a while and have sex.
 * Andrew: They are currently in a relationship through Books 5-8 and are presumed to still be dating.

In the television series, Spencer has been in relationships with:
 * Ian Thomas: They kissed and briefly dated.
 * Wren Kim: Flirted and kissed.
 * Alexander Santiago: Her current boyfriend.