He wanted free office space at the time, and Gru just offered his own house to him, which was a bit strange.
Now that Gru really meant to give it away, Cheng Daqi felt relieved, and the only doubt was resolved.
"Forget it, where's your new place? Make sure to invite me when you have a moving party,"
Cheng Daqi rejected Gru's 'kind offer,' which disappointed Gru considerably.
"It's just across from the LAPD headquarters, a regular small apartment, I doubt I will have a party,"
The crooked cop responded to Cheng Daqi with indifference.
"Why not have one?"
Picking up that the crooked cop wasn't telling the full truth, Cheng Daqi didn't call him out. Instead, he uncharacteristically prodded further.
"I'm not like you, Chan, you're still young, I'm already old."
This was Gru's genuine sentiment, the more he interacted with Cheng Daqi, the more he felt he wasn't being controlled by Cheng Daqi for no reason.