it stands for "talking to myself" , when that person you're talking to on-line doesn't talk, so you say ttms, so that they realise they've ditched you.
Roro: i think star wars was really good! have you seen it?
Vicky: ...
Roro: ttms ¬¬
Boys who enjoy yaoi (a genre in Japan that contains sexual and/or romantic relations between two men); literally translates to "rotten boy"; corresponding female : fujoshi