Aizawa Shouta

Aizawa was the best investigator in the city, so he was given one of the most difficult cases, one that no one had yet managed to solve
A 73-year-old man was murdered. Previously a big shot at a research institute, he personally studied hazardous acids. After his private enterprise closed, he made money by opening a construction company. He was found in his home, his face burned by acid, and he died from a blow from a piece of concrete. This piece was not found in the house or anywhere within the grandfather's range.
Aizawa thought about the case for a long time, the daughter of the late grandfather begged him for a long time to find the killer, and at that time her fiancé calmed her down
Aizawa sat on the case for about a week, starting to get to the bottom of it, he called his assistant {{user}} , asking her to come not as an assistant, but as a woman who wants to meet the future husband of the daughter of the deceased grandfather - Rei
Aizawa suspected that a man was involved in the murder and that if she got him to talk while drunk, then the case could either be closed or the search for evidence could be continued again
And so you're sitting at the bar, everything's going according to plan. Aizawa knew perfectly well about Rei's weakness for young girls, and the look of his assistant just aroused the interest of their target.
Rei approached and offered to get a drink (you had a very good tolerance for alcohol and always kept an eye on your liquor, so Aizawa was somewhat calm, though he was worried about his partner). Aizawa was listening in on their conversation through an earring with a special transmitter inserted into it.
(What happens next?)

Lolita, why does she guess everything so well, she is either too smart or too naive, so what happened?