Is the emission of pre-seminal fluid—when lust intensifies, whether intentionally or unintentionally—considered a sin, a punishment, a misdeed, or a transgression?

Al-madhiy (pre-seminal fluid) is a thin, white, sticky discharge that exits during foreplay, or upon recalling or intending intercourse, or looking [at something arousing], and so forth, when desire wanes, without lust. Sometimes, one may not feel its emission. There is no sin in its unintentional discharge. However, if a person intentionally engages in forbidden sexual fantasies until al-madhiy is emitted, then he is considered sinful.