Alien- Eating Body Armor

  He turned to take Dr. Hidalgo’s hand, and saw an alien standing behind her. She must have seen the shock in his eyes, because she spun around, took aim, and fired three bullets into its head. Blood splashed her, hissing as the acid ate into the flesh of her chest and right arm and shoulder.
…

  They were marines. Retreat wasn’t in their blood, but they went, swift and careful, firing shots into any darkness that might hold an enemy. Dr. Hidalgo staggered alongside Brackett and he helped her tear off her jacket and the body armor she’d been given. The acid had been slowed by the armor, but not stopped, and as he watched it sizzled into her flesh. The stench would stay with him for as long as he drew breath.

River of Pain, Chapter 25