Derek Waits is a male resident of Holby.
In January 2019, Derek published an online advert offering a free room for a woman on the condition that they would sleep with him. Desperate and homeless, Callie Timmens answered the advert and accepted the room.
On 18 May, Callie secretly tried to make a deposit on a flat, but Derek started knocking on the bathroom door. On their way down the stairs, he started recoiling in pain and fell, causing Callie to land on a vase. Once the paramedics arrived, Callie introduced herself as Derek's daughter, and they were both taken to Holby City Hospital's emergency department.
In resus, Derek told consultant Ethan Hardy about his flu-like symptoms, and staff nurse Jade Lovall mentioned that she once lived near Derek with a previous foster family. He claimed that he needed to call his brother-in-law, and Jade went to retrieve his phone from Callie. However, she heard Callie giving a conflicting home address to paramedic Ruby Spark and found her rent money in her bag. Derek admitted that she was not his daughter and that she was living in his house rent-free. Jade informed Ruby about Callie being Derek's tenant, and Ruby pointed out that there was only one bedroom in his house, suggesting that they were sharing a bed. Afterwards, Derek was diagnosed with hepatitis B, and he was adamant that he had no recent sexual partners. Nonetheless, he allowed Jade to inform Callie about his diagnosis.
Later, Derek was discharged, and Jade confronted him about his relationship with Callie; he maintained that it was consensual. He found Callie in her cubicle and offered her a taxi ride home, and, despite accepting the offer of a free room at a shelter, she agreed to go with him. (CAS: Series 33, Episode 35)