Chrono is a young officer of the Time-Space Administration Bureau and wields the S2U,a storage device in the first season and an ice-type Intelligent Device named Durandal in A's.His personality is usually one who looks at things from a logical approach,but he has made jokes on occasion.
His mother Lindy is his commanding officer and the Admiral of the Asura,while his father isnt mentioned(revealed in A's to be deceased.)Together they used thier influence within the TSAB to aid in Fate's trial,afterwhich he trained Fate in combat before her return in A's where she became his adopted sister.
In the first season Chrono displays his control over shooting-type spells when he aids Nanoha during the attack on the Garden of Time,so much so that Nanoha is speechless at his skill.As of StrikerS he has become the Admiral of his own ship,the Claudia while his mother lives on Earth next to Nanoha's home after retiring.
Seemingly the only thing that can catch Chrono off guard is Fate's habit of calling him "onii-chan".