Click on your two characters to choose what they do to choose the co-responding number next to the option (a.k.a 1 or 2) Abilities are explained here. Stealer (bandana guy) He is the support with one of his skills being Replenish which heals back 20 damage your duo took. His other skill is Steal he steals an item from the enemy making them sad and do less damage for 15 seconds Fighter (sword guy) Does a lot more damage then the Stealer. His first skill is Big Strike it is an extra large attack which always does a guaranteed 35 damage, but has a longer recharge then every other skill. His second skill is Pesky Attack. Fighter attacks peskily thus causing the enemy to be mad for 15 seconds which lowers there defense but increases there attack.
Emotions idea from OMORI