at the bottom of a stack / (figuratively) at the bottom of a hierarchy, unable to shine

a classmate (student of the same class) / a schoolmate who attends school in the same year

a person's actions, deeds, works, etc. / confessions and/or vows to follow Buddhist precepts / Short for 羯磨金剛 (katsuma kongō):

Synonym of 春風 (harukaze)