A pupil is a character created by another character. A master is the character that created the pupil. Characters obtained through the course of the story and monsters captured by throwing them on the base panel will not have masters.
Masters benefit from having a pupil in several ways. To illustrate these concepts, we will use three characters: Etna, Priest, and Mage. Priest is the pupil of Etna, and Mage is the Pupil of Priest
Masters can learn spells that a pupil has learned. To learn a spell from the pupil, the master must be standing on a panel adjacent to the pupil. The spell will show up on the bottom of the specials list as a level 0 spell with 0 experience. When any experience is gained for the spell, it will take its normal place in the specials list. When the spell gets to level 1, the master will know the spell permanately and can use the spell at any time, whether standing next to the pupil or not.
Using the example characters listed above, Priest will be able to learn spells from Mage. Etna will be able to learn spells from Priest, including any that Priest has learned from Mage. If Priest and Mage were both pupils of Etna, she would be able to learn the same amount of spells but Priest would learn less because he lacks a pupil.
Masters and pupils have an increased chance of performing combo attacks when one attacks with the other in an adjacent panel.
Using the characters above, If Etna and Mage are both standing next to Priest when he attacks, Etna and Mage have and increased chance of assisting him.
10% of the pupil's stats is added to the master. For example, if the pupil has a INT of 1500, the master gains 150 INT added to his own. Only the highest bonus between all pupils of the same master is added, so if Pupil 1 has 1500 INT and Pupil 2 has 1000 INT the master will gain the bonus from Pupil 1.
Assume the above mentioned characters have the following base stats: Etna - 2000 Int, Priest - 1500 INT, and Mage - 1000 INT. Priest will have a 100 INT bonus from Mage (10% of 1000). Priest's INT stat now becomes 1600 (1500 base + 100 bonus). Etna gains a 160 INT bonus from Priest (10% of 1600) and becomes 2160. If Priest and Mage were both pupils of Etna, her INT stat would be 2150 rather than 2160 because Priest would have no pupil bonus and only the highest pupil bonus would apply to Etna.
Note: Stat bonuses are only added to the master when the pupil levels up.
When a master transmigrates, he loses any stats gained from having pupils. When the pupil levels up again, the stat bonus will be reapplied.
When a pupil transmigrates, the master does not lose the pupil benefit, nor does it decrease because of the pupil's lowered stats. Assume Etna has 1150 INT (1000 base + 150 from her pupil). The pupil has 1500 INT. When the pupil transmigrates it has an int of 100. Etna's INT remains at 1150 even though the pupil stat bonus would only be 10. When the pupil level up enough to have an INT greater than the INT he had before transmigration, Etna's stat bonus will increase to match.
Note: If the master transmigrates after the pupil has transmigrated, the master will lose the stat bonus gained from the pupil when it was higher level, and will only gain the stat bonus of the now lower level pupil.