Benefits (How this will benefit the server and game as a whole): Marines have a chance to fight back against their assaulters, xenomorphs can actually have a more reliable method of capturing Marines that don't involve huggers or slashing them to pain crit. Fits well into the lore of CM and makes use of the the powerful strength and reflexes xenomorphs are known to have.
Details (Description of how you think this would work, the benefits, etc): Similar to a reinforced grab for Marines, grabbing a mob will bring up a grey box in the active hand the player in question is using and clicking that box will upgrade the grab to a reinforced one. It can be resisted out of but it will take time, depending on the caste, level of hunger the Marine is in, and the Marine's health. Marines' ability interact with their environment (as in, pick up/hold items or use a console) will be nullified until the grab is completely resisted. Xenos can't slash the mob, but still can be attacked by outside forces.Devouring for humans by any xenomorph while the grab is active is disabled. The mob in question is hidden under the xenomoph, during the grab, and the only damage they can directly suffer from is the occasional acid splash or AoE effects (i.e fire, explosions, gas clouds) but receive half the damage they'd normally take. The instant the passive grab is in the process of being upgraded, a bolded black text message pops up alerting the players of the situation, prompting them to act quickly. If frenzy is active, the upgrade time is reduced to 4 seconds. As a final point, while the grab is active, it will also drain plasma, albeit at a slower rate (15/t) very detrimental for spitting castes.