It happens increasingly often that experts need to collaboratein order to exchange ideas, views and opinions on their path towardsunderstanding. However, every collaboration process is inherently fragileand involves a large set of human subjective aspects, including socialinteraction, personality, and emotions. In this paper we present Pogat,an affective virtual agent designed to support the collaboration processaround displays by increasing user awareness of the group affective tone.A positive group affective tone, where all the participants of a groupexperience emotions of a positive valence, has been linked to fosteringcreativity in groups and supporting the entire collaboration process. Atthe same time, a negative or inexistent group affective tone can suggestnegative emotions in some of the group members, emotions that canlead to an inefficient or even obstructed collaboration. A study of ourapproach suggests that Pogat can increase the awareness of the overallaffective state of the group as well as positively affect the efficiency ofgroups in collaborative scenarios.