"The Russian Embassy in Bulgaria has issued a note demanding that its former Soviet–era ally clean up the monument in Sofia's Lozenets district, identify and punish those responsible, and take 'exhaustive measures' to prevent similar attacks in the future, the news agency reported Monday.
The monument was spray–painted on the eve of the Bulgarian Socialist Party's celebration of its 123rd anniversary, the Sofia–based Novinite news agency reported.
The vandalism was the latest in a series of similar recent incidents in Bulgaria – each drawing angry criticism from Moscow.
Early this year, unknown artists painted another monument to Soviet troops in Sofia in the colors of the Ukrainian flag.
In August last year, a Soviet army monument in Sofia was painted pink in an 'artistic apology' for Bulgaria's support of Soviet troops who suppressed Czechoslovakia's Prague Spring revolt against Moscow–based communist rulers."
(Anna Dolgov, 19 August 2014, The Moscow Times)
"Throughout our society there tends to be one informal or backstage language of behaviour, and another language of behaviour for occasions when a performance is being presented. The backstage language consists of reciprocal first–naming, co–operative decision–making, profanity, open sexual remarks, elaborate griping, smoking, rough informal dress, ' sloppy' sitting and standing posture, use of dialect or sub–standard speech, mumbling and shouting, playful aggressivity and 'kidding,' inconsiderateness for the other in minor but potentially symbolic acts, minor physical self–involvements such as humming, whistling, chewing, nibbling, belching, and flatulence. The frontstage behaviour language can be taken as the absence (and in some sense the opposite) of this. In general, then, backstage conduct is one which allows minor acts which might easily be taken as symbolic of intimacy and disrespect for others present and for the region, while front region conduct is one which disallows such potentially offensive behaviour." 
(Erving Goffman, 1959, p.78)
 It may be noted that backstage behaviour has what psychologists might call a 'regressive' character. The question, of course, is whether a backstage gives individuals an opportunity to regress or whether regression, in the clinical sense, is backstage conduct invoked on inappropriate occasions for motives that are not socially approved.
Goffman, E. (1959). "The Presentation of Self in Everyday Life", University of Edinburgh Social Sciences Research Centre.