The Emotion-Suppression Spell is a Hedge Magic spell used to store the caster's emotions in a flask.
In 2016, to prepare for their journey to Fillory, Quentin Coldwater, Alice Quinn, Eliot Waugh, and Margo Hanson sought out Kady Orloff-Diaz for information on how to properly cast Battle Magic. Diaz explained that battle magic would take a decade of discipline for the group to properly master, but there was a spell used by Wedge Witches to facilitate the need for emotion control.
At the Physical Kids' Cottage, the group performed the spell, trapping their emotions in small phylacteries around their neck. However, Quinn and Penny were against using the spell and instead opted to meditate in order to practice without it. When Coldwater, Waigh, and Hanson completed their training, they celebrated their success and slept together, causing Quinn to break off her relationship with Quentin the next day.