Original SCP Entry: http://www.scpwiki.com/scp-153

Specimens of SCP-153 excrete a highly acidic substance similar to [DATA EXPUNGED] from their mouths and gullets, and they have the ability to camouflage themselves both outside and in. SCP-153 has developed a hunting technique where a specimen will swim up a shower or bathtub drain, dissolve the drain cover with its acidic saliva, and camouflage its gullet to look like a standard drain. Shortly after a human enters the shower or bathtub, the specimen [DATA EXPUNGED] back down the drain, leaving almost nothing behind. This entire process usually takes less than █████ seconds.