if you're talking about the cousin's son's death then yes. from what i've understood, the son killed mimi by driving over mimi. minyeong later on killed the son the same way the son had killed mimi. that's why minyeong said something by the lines "did you like the present i sent you?" while looking up at the ceiling (sky) if yk what i mean.
nah i think i messed up with what i just said. from what I'VE understood, someone else in the comments from before explained it a little differently. but it says in the chapter that minyeongs uncle (that older man that sat besides cheol) he had a cousin and that cousin had a son. and that son had killed the family's dog (which is probably mimi??) and that bastard (seems to be adressing the son) dragged mimi away and ran her over. and do you guys notice a pattern? the son got killed in a car accident (minyeong's doing) and so did mimi (son's doing). but later in the chapter, i didn't quite understand what minyeong meant with mimi protecting minyeong. the cousin or the son's cousin (dunno which one) had tried to kill minyeong, but mimi stepped in and got killed for minyeong, so he wouldn't take the damage. and minyeong not understands why mimi did that, since he has someone special (cheol) that he want to do the same for.
For the part you don’t understand, he want talking about Mimi protecting him. He was at his parents shrine and was thanking them for protecting him in the car crash that they died in so he could keep living and meet Cheol. After he finishes speaking to his parents he talks to Mimi and asks if she likes his gift of killing her killer

still feeling like that one future image with the hand behind his head. what did the uncle exactly mean?? Did Minyoung plan the death himself or??