Notes: This straddles the line for T and M for me, so I'm playing it safe and going for M in case my judgment for a lower rating is so very wrong.
Stats: 500 words for ChromRobinTharja. Not smut like A queen's desire was, just some dubious consent and voyeurism. Just that, you know? ...gosh, I'm an awful human being.
Robin woke up to the feeling that she was being watched intently, Chrom spooning her in their bed. In the darkness, she could barely make out the shape of a person standing by her side; to say she got startled would be an understatement, as she screamed and elbowed her husband.
"Ugh... What is it...?"
"You aren't having sex, why?" Tharja's voice asked plainly.
"Tharja? What are you doing in our room?" Chrom asked, now alert and holding his wife closer.
The tactician could only groan, pulling the blankets up. "Tharja, get out. We're trying to sleep."
"I know," the dark mage said, sounding confused. "But you two always have sex every third night. I was wondering what's wrong tonight."
"Wait, what? For how long have you been spying on us?"
"Tharja, I thought you had stopped stalking me during my sleep; you promised when I married Chrom."
"But sex is not sleeping." Dear Naga! "I have been keeping track of your schedule. You always follow the pattern, unless you're ill." Gods! "So, what's wrong tonight? Can I help you two? Should I fetch a healer?"
She just wanted to cry in shame now, turning around to hide her face against her husband's chest. He held her and tried to fix things: "Tharja, please leave. We'll talk in the morning, if you want." His wife certainly hoped she wouldn't!
The dark mage completely ignored him. "Robin, should I face away? Hide behind the dresser? Do I work him up a bit for you while you get in the mood?"
The tactician was convinced she was having a nightmare. There was no way something like this was happening to her. Yet, no matter how much she pinched her arm, she was not waking up...
"I have practiced a spell that could help you with that last part. Let me cast it on him, and see if you like it."
"Tharja, no!" ...but it was too late; Chrom had been hexed.
Her protests were drowned out as he kissed her more passionately than ever before, apparently overcome with mad lust for her. She nearly forgot the dark mage was standing there watching them for a moment, but as her husband's kisses trailed down her neck, her collarbone, her chest... she looked up and saw the devilish smirk on Tharja's face.
She shut her mouth tight to keep her moans in while she tried to gather her thoughts. She had little time left; her husband had already disappeared under the covers.
"Leave now."
"Isn't it a marvelous curse?"
"Leave."
"Don't be upset. I can cast it on you as well."
"Tharja, stop!" ...she lost once more; Robin kicked off the blankets and bed sheets, reaching out to pull Chrom closer to her lips again.
The dark mage stood there, watching silently, feeling so very hot, as she always did when she checked in on them. She had employed a dirty trick to get them going, but it was very worth it. For her.