A/N In the world of Buffy the She-Mantis assuming the identity of a teacher in order to lure virgin males to her home in order to mate with them and then eat them seems like a long way to go when she could have just grabbed some off the street around the Bronze. She scared vampires, she had to be strong enough to do just that. On the other hand, there's a mantis Wesen and they're normal behavior can be used to explain why the She-Mantis would go to all that trouble. Although only the male is mentioned on Grimm and no mention of females is made at all. As for why a human male verses a male mantis, there's precedent in Grimm to explain that too. Male Wesen of some subsets of Wesen can't reproduce at all, the females have to reproduce with normal humans. No explanation is given for why the males can't reproduce, but that wasn't the point of the episode anyway. ;)

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Xander was talking to Cordelia when he noticed a woman walking towards Jesse. Only she wasn't a normal woman.

"Excuse me, could you direct me to the Science building? Room 109?"

"Um, yes, I go there everyday. It's a, over there, uh." Amy frowned as Jesse stuttered trying to answer a easy question.

"It's down the hall, that way." She told the woman. "On the the right side of the hall."

"Thank you." She looked back at Jesse. "Perhaps I'll see you there later."

"Oh yeah! I hope that too!" He enthusiastically agreed and couldn't take his eyes off of her as she walked down the hall.

Amy snapped her fingers in front of Jesse's eyes. "Jesse, what has gotten into you? I know she's hot, but I thought you were working on not being an ass in front of me, your girlfriend."

"I don't think it's his fault, Amy." Xander told her, as he and Cordelia walked over to the couple. "On account of that's a Wesen and I think she's using pheromones."

"What like a Zeigevolk would?" She asked, alarmed.

"Probably, I'm going to talk to Principal Flutie and cut class. I need to know if she's a danger to anyone. I've never seen a Wesen like her."

"So not one of the Wesen that live here in town." Cordelia said. "There's several dozen kinds here in Sunnydale."

"Yeah and as I told Buffy, it's out of towners that tend to cause a problem and some of them come here on purpose, to test themselves against Grimm. Keep an eye on Jesse, if she is using pheromones, than he has little to no control over his actions right now."

"We'll keep him on a lease." Amy promised. "I can use a spell to blunt the effects of any pheromones she's giving off. It's temporary, but he just needs it to get him though the class period anyway."

"I'll be back as soon as I can." He kissed Cordelia and went to find Principal Flutie. Once it would have surprised him that the Principal of his High School was actually other then a normal human, a standing joke kids had was that their teachers weren't actually human, after all. Principal Flutie was alarmed at the idea of an unknown Wesen in his school and very alarmed at the idea that it might be using pheromones on his students and quickly wrote Xander a note to excuse him from class. Xander headed straight for Uncle Rory's.

"What did her woge look like?" Rory asked.

"Like a giant insect, total body woge."

"Insect? I've never dealt with an insect Wesen before, there are several different kinds though. Here, you look through that book and I'll look through this one. We'll figure this out, hopefully before she causes any trouble. Just the fact that she may be using pheromones suggests she's up to no good."

After hours of reading though different books, with Rory showing Xander pictures of the ones he came across and asking if this matched and Xander saying no while coming up with nothing himself, they finally found something.

"This one, Uncle Rory, I'm sure this is the Wesen I saw, at least a female version of it."

"Sairento Shi, mantis Wesen. Stealthy, careful and precise. In Japan they could be found among the ninja. Known to be very cautious and thorough. Their arms are serrated and blade like, able to actually be used like a sword because they're sharp enough. The males can't reproduce so the females need to mate with normal humans when they're in season. Xander, they consume the humans they mate with and they prefer virgins."

"Ah crap, as if being a virgin isn't already an all consuming negative to a teenage boy and let's not forget the virgin sacrificers. How do we deal with her?"

"She's sensitive to bat sonar and it stuns her. After that, we can just kill her with swords."

"This is one of those no win situations I hate, Uncle Rory. She wants to be a mother, continue her species, whatever, and she has the right to do that. But to do it she needs normal human males and she eats them. If she didn't use pheromones and the human male could give consent, it would be none of our business. But the pheromones and eating males makes it our business. We have to kill her and where do we get bat sonar?"

"Leave that part to me. I know a Murciélagos, basically a bat Wesen, that lives in Ojai. It shouldn't take him long to get here. He owes me a favor. He can record his shriek before he gets here and we can use it on her. With proper protection because his shriek can literally shatter glass and do considerable damage to a human."

"Which means we also need to make sure any victims are safely removed before we even use it. I think we need some help with this one, Uncle Rory. Buffy can help us."