Sayyiduna Abu Hurairah (may Allah be pleased with him) said: The Messenger of Allah (peace and blessings be upon him) said: "Whoever goes to sleep while there is the smell of grease on his hand (i.e., sleeps without washing it), and then something harms him, then he should blame only himself."
Hadith Referenceسنن دارمي / من كتاب الاطعمة / 2100
That is, if a person who sleeps without washing his hands suffers any harm, then it is his own fault and no one else’s, because he did not sleep after thoroughly washing his hands. Therefore, if due to the smell of food or greasiness, he is bitten by a mouse or stung by an insect, then this is the result of his own action. In this, there is both encouragement and warning regarding washing the hands after eating, which is among the etiquettes of eating.
Here, the term "Bab al-Wudu" does not refer to the ritual ablution (wudu) in the legal (shar‘i) sense, but rather only to the washing of the hands.