Backward crosstalk effects (BCE) are observed in dual-task studies when characteristics of Task 2 influence Task 1 performance. When Task 2 is a go/nogo task, responses in Task 1 are slower when Task 2 is a no-go as compared to a go trial. This no-go BCE has been argued to be due to response inhibition spilling over from Task 2 to Task 1. Growing evidence shows that response inhibition elicits negative affect leading to affective devaluation of associated stimuli. We tested for a functional role of the negative affective consequence of response inhibition in the no-go BCE by investigating its interaction with affective processing in Task 1. In four experiments, Task 1 was a valence categorization task, and Task 2 a go/no-go task. In all experiments, the no-go BCE strongly depended on affective processing in Task 1. While this modulation could be attributed to an affective (mis)match between stimulus features in both tasks in Experiments 1 and 2, Experiments 3 and 4 provided evidence for an affective (mis)match between stimulus valence in Task 1 and affective consequences of Task 2 response inhibition. Results are discussed in the context of current theories of no-go BCE in dual tasks.