remorseful

As an adjective remorseful

is (of a person) feeling or filled with remorse.

As a verb expiate is

(transitive|or|intransitive) to atone or make reparation for.

As adjectives the difference between guilty and remorseful

is that guilty is responsible for a dishonest act while remorseful is (of a person) feeling or filled with remorse.

As a noun guilty

is (legal) a plea by a defendant who does not contest a charge.

As adjectives the difference between remorseful and compunct

is that remorseful is (of a person) feeling or filled with remorse while compunct is (obsolete) affected with compunction; remorseful.