Bird Time is the only way to raise any character's support level with Eshmel during Part 1 in Fire Emblem: Fortune's Weave. Whenever characters interact, either in or out of battle, they can gain support points. However, Eshmel is only a bird throughout the first routes, and you can't control them. Your only option to form a bond between them and the other characters is by having a quick chat with Eshmel at the Perch — an activity similar to the tea time in Fire Emblem: Three Houses.