This term when used over email, is a substitue for such words as sex,boned, and penetrated. More often than not, invest is used in place of these words to keep The Man from getting wise about conversations that are not clean enough to make it through corporate email filters.
Jim: This chickwanted to invest the hell out of me me she had large assets, but her portfolio smelled like rotten salmon.
Dave: I hate it when a girl's commodities are rotten.
Spending your time and money for your own improvement, future success or good time / enjoyment. As opposed to spending your money and / or time trying to please people especially people you don't like.
" I can't believe it! I just blew her rent money hosting a big dinner party for my frenemies."
"Yeah it sounds like you don't know how to invest in yourself. "