Bellaquera is a colloquial and somewhat vulgar term in some Spanish-speaking regions, particularly Puerto Rico, that refers to a state of intense sexual arousal or horniness.
In the context of this song, Nicky Jam uses it to playfully excuse his actions and words from the previous night, attributing them to his "bellaquera" (lust). He sings, "Bebé, échale la culpa a mi bellaquera" (Baby, blame it on my horniness), implying that his desires led him to say or do things he might not otherwise. It's a raw and direct word that captures the song's explicit themes.
The whole song sits in the hour after a club closes and before anyone has slept. It opens with "Ya es de madrugada" (It's already early morning) and a narrator too far gone to feel his own face, leaving with someone he has no plans for. There is no romance on offer and the song is blunt about it. "Mami, yo no quiero boda" (Mami, I don't want a wedding) is the hook, sung over and over against "un poco de codeine en la soda" (a little codeine in the soda), until the point is impossible to miss.
What Dei V offers instead of a wedding is a shopping list. "No hay wedding ni en la Hermes, dime qué cartera quieres" (There's no wedding even at Hermes, tell me what purse you want), then dinner at COTE, then a plane or a boat and "tú decide' dónde" (you decide where). The excuse turns up at the end and it is at least an honest one: "Bebé, échale la culpa a mi bellaquera" (Baby, blame it on my lust). It is a good listen and a fairly dismal proposition, and the song knows both.