You and Andrea took barely three steps from the stairs when you heard the low growl of another lizardperson followed by some clanging of metal furniture and an unmistakably human, "No, please!" Without hesitating you both sprinted as fast as possible to the security room where you had heard the commotion and turned to look inside. What you saw was the back of a serpantine lizardperson who had pinned a human against the corner between the wall and some metal cabinets, the torn sleeve of a lab coat as the human struggled against-
That's all you needed for you and Andrea to take action. You immediately dropped the metal box on the desk and blitzed the serpentine with a roar, focusing your strength on separating the lizardperson from the victim by pinning the former against the back wall. You hear the angry hisses of your opponent as you struggle to keep the snake pinned, using a claw to keep those fangs away before you hear the crack! Crack! of the rifle Andrea was carrying before you feel the gigantic snake being go limp and hiss out of life. With a low growl you heave the now-dead serpentine lizardperson off yourself, checking to make sure you're more-or-less clean before turning to look at who you managed to rescue...
...kinda. As you're turning to see but before you even see them, the smell gets to you -- the smell of lizard seed. Damn it, you weren't able to stop it in time. You look down at the trembling human in the torn lab coat and splashed with glistening- you already know what's happened and quickly look up at Andrea at the door, letting out an urgent growl and pointing to the metal box you left on the table. Andrea lets out a quick "OK" (or, at least you assume that particular growl was what that meant) and picks up the box before hurrying over.
You look back down and look more closely, though keeping your maw way up in order not to try to terrify them further...and your jaw hangs open as you see who it is: Nicole Chase, another researcher from this lab (though on another team so you didn't really know her)...and as evidenced by Andrea stopping next you and letting out a growl of surprise, her sister.
Andrea goes down on one knee calling her name with her reptilian voice to try to comfort her sister, but stops when she cries, "Stay back!" Andrea stops, the hurt on her face evident to you before she realizes right now she looks like the monster that just attacked Nicole - she has no idea her sister is here. Andrea quickly grabs the two ID cards and gently lays them on the ground for Nicole to see, before scooching back and allowing her to see: "...Richards?" Nicole's voice is full of disbelief as she looks at Andrea who's pointing up at you; you nod your head with a low hiss in affirmation. She looks down your now-male body, lingering a bit on your still-erect-but-not-painfully-so dicks out of confusion before looking back at Andrea, who's now doing some series of hand motions with her claws that honestly look childish. You let out a confused growl before you see Nicole's hands start to copy Andrea's movements, and then you realize what's going on: it must be some kind of secret handshake or something the two sisters made when they were little, and Andrea's performing them now to prove that she's the sister Nicole knew, at least in mind if not in body. Nicole gasps when she realizes as well: "Sis?!" Andrea nods more emphatically than you did, a hopeful purr escaping from her maw. "But how-" Andrea slides the metal box over, which Nicole recognizes right away. "The antidote...it worked?!"
You were just able to let out a growl of affirmation before Nicole suddenly seized up in pain, her hands clenched then splayed open almost involuntarily as the nails start to lengthen into familiar claws. No time to waste - Nicole needed the antidote shot now.