= Solution
<Pyrrolidine> and 2-methylcyclohexanone first form an <enamine>, through <carbonyl> addition, <carbinolamine> formation, dehydration to an <iminium ion>, and alpha <deprotonation>. The less hindered <enamine> <carbon> is on the side opposite the methyl-bearing alpha <carbon>. It attacks the terminal beta <carbon> of <methyl vinyl ketone>, while the conjugated $\pi$ system shifts to <oxygen>. Protonation gives an alkylated iminium species; aqueous acid then hydrolyses it back to the <ketone>.
The result is a <Michael addition> product: the previously unsubstituted alpha <carbon> bears $-\mathrm{CH_2CH_2COCH_3}$. In drawing the arrows, start the new C–C bond at the <enamine> <carbon>, not at <nitrogen>. The iminium bond is restored during addition and removed by <hydrolysis>. The sequence is an enamine-mediated conjugate addition, rather than direct addition to the <methyl vinyl ketone> <carbonyl>.
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