THIS IS ALSO POSTED ON AO3 Y/N started at the BAU almost 2 years ago and her and Emily's bickering started on her first day. The pair constantly throw insults at each other along with glares and eye rolls, the team are used to their petty arguments - it doesn't stop them from solving cases together. What will happen when the pair have to go on an undercover mission as a couple, will living together change the dynamic of their relationship? Will new feelings be recognised?

𝐑𝐞𝐝 𝐑𝐨𝐨𝐦 𝐱 𝐂𝐫𝐢𝐦𝐢𝐧𝐚𝐥 𝐌𝐢𝐧𝐝𝐬 𝐊𝐚𝐭𝐞𝐫𝐢𝐧𝐚 𝐒𝐨𝐤𝐨𝐥𝐨𝐯, five years ago, escaped the Red Room and helped the CIA burn it to the ground. She thought she'd destroyed the monsters that made her. She thought her little sister, Nadia, made it out too. She was wrong. Now, young girls are vanishing across the globe. Families with ties to organized crime are turning up dead. And the Red Room has returned--smaller, smarter, more dangerous. When the CIA identifies a pattern that only one person would recognize, Katerina is pulled out of hiding and sent to Quantico to work with the FBI's Behavioral Analysis Unit. Dr. Spencer Reid doesn't know who Katerina really is-not yet. But as they investigate the dark psychology behind the kidnappings, their bond deepens, and so do the secrets she's been forced to keep. Together, they'll uncover the truth about a program that was never truly destroyed. And somewhere in the shadows, Nadia is still watching. trope: strangers to lovers spencer reid x female oc PLEASE DON'T BE A SILENT READER!!!