Serena wakes beside Koen after the night they spent managing her fever and arousal. When Sem calls with possible news about Serena's condition, Koen immediately assumes Sem's partner has identified the real issue and takes Serena to Sem's office for what he jokingly calls a biology lesson.

At the office, Sem quickly yields to Layla, a midwife with experience treating Weres. Layla explains that Serena's doctors focused so heavily on cortisol and CSD that they missed the larger pattern in Serena's blood work and symptoms. Serena is not simply getting sicker in a conventional way: she is going into estrus, or Heat, in human form. Layla says breakthrough heats can happen when shifting is blocked and can be triggered by stress, medication, or close proximity to a sexually compatible partner, and Koen's lack of surprise makes clear that he has already guessed much of this.

Layla then describes what Serena should expect before the Heat fully begins. Serena's fevers, low appetite, aches, and inability to shift fit the pattern, and the worsening nighttime episodes suggest the estrus is close. Layla warns that Serena will likely begin nesting by collecting soothing fabrics, scents, and objects, which makes Serena realize that her attachment to Koen's flannel and her stockpiling of blankets were instinctive nesting behavior. Layla also says Serena's scent will become more attractive to potential partners, and Koen confirms that this has already begun. When Serena worries about other Weres approaching her, Koen promises that anyone who touches Serena without her consent will be hurt and killed.

After Serena asks Koen to leave, Layla speaks plainly about the part everyone was avoiding because of the covenant binding the Northwest Alpha. During estrus, Serena will want sex intensely, may struggle to think past arousal, and will need isolation with a chosen partner for two to five days. Layla says trying to endure it alone would be miserable, that Weres generally view Heat as a practical and often pleasurable bonding event, and that increased fertility is part of its biological purpose. That last point forces Serena to confront the possibility of pregnancy, even if her hybrid genetics make it uncertain. Overwhelmed by what estrus would demand from her body and from Koen, Serena ends the conversation by asking Layla to make sure she does not go into Heat at all.