Accept it

"Very well. I glad that you became smarter" You answer. Getting more swords to fight in future war with orcs is more important than anything else. Besides you can push for harsher conditions later

"Thank you. " Sheila answers and points to her left "It's Reeza. She is second in command for now. You can discuss details with her" With that words Sheila falls from her horse unconsicious. Turns out she is badly injured and needs medical treatment now.
_____

Soon you were back in your camp, Seila brought to tribe's healers it was found that she has nothing more severe than arm injury and collapsed from a combination of blood loss and exhausting so she needs some time to recover. Some time you may spend with her assistant

"So, Reeza, explain me the situation. I think you lost the battle?" That girl is very similar in appearance to Sheila, most likely they are sisters. Still they are different, Reeza is calm and collected, not emotional like Sheila

"We lost, most died, some enslaved by orcs, we ran away to join your tribe" She answers calmly "Somehow Sheila believes that you will treat us equals. I'll not question the judgment of my leader"

"But you and most of your tribe are sure that I'll trick you and use your sisters as sex objects?" you make a guess only to get a nod from the amazon " Then why you agree to that conditions?"

"It's better then to become slaves of the orcs. I know that from personal experience. And I am ready to be fucked if that will leave me a chance to **** that bastards. Please, whatever you'll do don't disarm us. Let us fight with that bastards " Reeza is calm and determined and you think that Amazons did wrong choice choosing temperamental Sheila over Reeza

"I don't need every woman in the tribe" You say smiling " I will be content with few human lovers, I like your bodies. Should three or four of you agree to belong to me, others may not give their bodies to my subordinates" Passing opportunity like that would be stupid. If Reeza is ready to give her body to you, there are no need to refuse even if it wasn't your intentions

"I think I'll find two others beside me" Reeza says lowering her gaze "I only ask you keep our contract in secret. She will hate both of us for that, no need for her to know."