Actually it means, Standard Operating Procedure

Commonly used in text messages or social media as a short form for Very Sound Advice.

Standing Operating Procedure (SOP) - Commonly and erroneously referred to as Standard Operating Procedure. Written military directives defining the actions to be taken upon the occurance of specific events.

Someone who is soppy: overly emotional, overly romantic, and generally being a wuss. You wouldn't call yourself a sop, you'd call someone who wasn't being hard enough one. Commonly used in the UK.

Acronym for Semen on Picture. Similar to a Cum Tribute, SoP is the act of cumming on a picture of a female celebrity, anime character, hentai, video game character, or even a picture of a personal request. Can mostly be found on Pornhub or xhamster websites.

to soak up gravy or other liquid like foods with bread or other material

Standard Operating Procedure. Things that are routine and come naturally to a person. Commonly pronounced as "soppy"