What is the ruling on a husband kissing his wife's mother on her mouth, jokingly and forcefully?

"What the husband does, kissing his wife's sister on the mouth, is impermissible in Islamic law. It is a pretext for temptation and falling into the forbidden, because the mouth is a place for passionate kissing. His action is not justified by his statement that 'she is like his mother,' as it is not permissible to kiss maharim (unmarriageable kin) on the mouth. Jurists have stipulated the permissibility of kissing maharim upon returning from a journey or similar occasions with conditions, including: the absence of lust, that the kissing is not continuous but only on special occasions, and that it is not on the mouth but on the forehead or head. Islamic law has blocked all pretexts leading to indecency, prohibiting everything that leads to it, including passionately kissing anyone, even if they are maharim."