Computer systems are designed and used by humans. And human being is characterized, among other things, by emotions. Giving this fact, the process of designing and developing computer systems is, like any other facet in our lives, driven by emotions. Requirements engineering is one of the main phases in software development. In Requirements engineering, several tasks include acceptance and negotiation activities in which the emotional factor represents a key role. This paper presents a study based on the application of affect grid by Russell in requirements engineering main stakeholders: developers and users. Results show that high arousal and low pleasure levels in the process are predictors of conflictive requirements.