Lukas Summers HarrisEdit
- Kassidy: "Are you alright?"
: Luke: "I'll live. You know that guy is right, I won't let aunt Buffy kill you. You saved me and Jayde."
: Kassidy: "But I still killed them."
: Luke: "Only to save us, Kassie."
- -Luke tries to stop Kassidy blaming herself.
Lukas Summers Harris is the son of Dawn and Xander, making him Kassidy's cousin. He was born a few years after Kassidy but they are still close. Since Kassidy doesn't have any proper siblings, Lukas and Aimee are the closest she has to any. Kassidy is at first unsure of Luke as he refuses to get to know her after his girlfriend Leila tells him, she will be returned to Riley anyways after she had getting to know her mother out of her system. But when Kassidy began to doubt her welcome, Luke ignored Leila and began to introduce Kassidy to the others like Sarah, Jennifer, Jayde, Oliver and Kelden. When Luke was kidnapped a year later with his new girlfriend, Jayde, Kassidy killed the people who took them after finding Luke physically beaten and Jayde, emotionally so. Luke told Buffy what happened and swore Kassidy had done it to protect him and Jayde.
Aimee Summers HarrisEdit
Aimee is the younger cousin of Kassidy. Sister of Lukas. She and Kassidy get on straight away.
- Kassidy: "I can't believe you have my speech."
: Ryan: "Oh, darling, you have no idea what I had to do to get it."
: Kassidy: "Oh and what was that?"
: Ryan: "I'll never tell."
: -Kassidy jokes and bonds with Ryan at the Miss Sunnydale event.
When Ryan first arrives in Sunnydale, he meets Kassidy at the Bronze as she is trying to annoy Jake by hitting on the bartender after he hits on the waitress. Feeling embrassed as Ryan witnesses the childish attempt at hitting on the bartender to get back at her boyfriend, Kassidy tries to apologise as Ryan says he gets it but it's also not a good sign in a relationship. As Kassidy ponders if Ryan is right, he disappears and she is left alone to think about what he said. The next day, Kassidy breaks up with Jake, stating they aren't good for each other. She later runs into Ryan again at the 'Miss Sunnydale' event being held in which her younger cousin; Aimee is involved in. Ryan and Kassidy sneak off to drink some champayne before he mocks her for having being a Miss Sunnydale, the year before. She laughs and Kelden watches as she begins to bond with Ryan. A few weeks later, Kassidy is told her cousin Luke and best friend Jayde were taken by witches and she asks Ryan to help her trace their whereabouts. When they find her cousin physically beaten and Jayde mentally abused, Kassidy loses her temper and kills the witches for hurting them. The next morning, Kassidy begins to panic as her mother swore if Kassidy killed anyone, Buffy would kill her. Ryan comforts her and states that her cousin saw everything and knows it was for his and Jayde's benefits that Kassidy killed their kidnappers. Kassidy relaxes and they return to the Summers' household to explain everything. At first, Kassidy waits outside with Ryan, afraid for the outcome but Buffy embraces Kassidy as Ryan leaves. After an arguement with Kaylee that led to Kaylee changing and biting Kassidy, Ryan steps in and offers to save her life. When he feeds Kassidy his blood, Ryan explains that he is a rare breed of supernatural. A hybrid. Half vampire and half werewolf. His blood can save anyone bitten by a wolf, but that she must keep it to herself. Kassidy agrees to keep his secret, and returns the favour of saving his life as Jake loses his temper and deliberately stakes Ryan in the back. Kassidy removes the stake and realises she is starting to fall in love with Ryan but pushes away her emotions. Ryan sends Kassidy a beautiful gown on the night Keir and Isabelle host a dinner party at their home. When she turns up, he is stunned by how beautifully she wears the indigo gown. At first, Kassidy is uncomfortable and goes to see the horses outside, causing Ryan to follow her and share stories of his past before asking her back inside to dance and toast to the hosts. On the night of Kassidy's Prom, Ryan tells her that he is leaving Sunnydale because there is nothing to keep him there. Feeling a sense of loss, Kassidy finally admits how she loves Ryan and he kisses her cheek, saying he knows. Asking him if he is still leaving, Ryan says he's sure he can find something to make him stay before kissing Kassidy.
- Kassidy: "I tried not too, but I can't help it..."
- Kelden: "I know, Kass. You see so much good in others."
- Kassidy: "I'm so sorry, Kelden."
- Kelden: "One last kiss before we become friends."
- -Kassidy and Kelden break up
Kelden Osbourne is the son of Daniel Osbourne and Bayarmaa, Kassidy's first love and first supernatural boyfriend. Kassidy and Kelden bonded as she began to date Oliver Thurman, Kelden's best friend. The pair showed a deep friendship and adoration for each other, especially when Jake began to try and win Kassidy's heart. At first, Kelden showed signs of jealously and began to form a friendship with his Pack leader's [later sister as Owen takes over] daughter; Kaylee Fuller. This caused friction between Kassidy and Kelden as she believed that Kaylee was actually in love with Kelden and the pair briefly broke up before reuniting after Sarah and Jayde force them to face their issues. Kelden's issue being that Jake was deliberately trying to break them up and Kassidy's being that Kelden forming a friendship with Kaylee had caused the other girl to fall deeper in love with him. But after discussing things, Kassidy and Kelden reunited for a few months before Kassidy became a vampire. After Kassidy's transformation, she originally pulled away from Kelden as Jake had told her that werewolf bites were like poison to vampires and she didn't want Kelden to blame himself if it happened accidently. As everyone found out about Kassidy's transformation, Kelden stuck by her side and promised to protect her from the other Slayers and Potentials. When Kassidy began to spend more time with the West brothers, the more she began to develop a deeper connection to Jake, even though she tried to fight it because of her love for Kelden, she couldn't. Kelden could tell that something had shifted between them, even though they remained friends, their love had changed. Kassidy admitted that she had feelings for Jake and the pair agreed to remain friends for the sake of everyone and them not wanting to lose each other. At the Senior Prom, Kelden was the first one to dance with Kassidy.
Sarah Louise GilesEdit
Jayde Stacey WoodEdit
Keir Keppler is the older brother of Isabelle and arrived in Sunnydale after hearing rumours of his progeny; Jennifer causing trouble. He is also the Sire of Nathaniel and Jacob West. Keir is annoyed that he has to chase up Jennifer and that she caused a Slayer's daughter to become a vampire. Even though Jake is the one who is Kassidy's Sire, Keir takes her under his wing as Nathaniel does and teaches her things that Nate doesn't know yet and that she is more powerful than any normal vampire because of her Potential Slayer status. Kassidy warms to Keir instantly as he shows more intension of teaching her than Jake.