An Obuasi Circuit Court on Tuesday sentenced a 20-year-old adopted son, David Adofo to 15 years in prison, for defiling his 13-year-old sister on countless occasions.The court, presided over by Gilbert Ayisi Addo, found him guilty of the offence.The victim's grandfather had adopted the convict one-and-a-half years ago and was living with them in their apartment at Gausu Extension at Obuasi, in the Ashanti Region.Adofo volunteered to teach the Junior High School form one student but shamefully took advantage of the situation to have sexual intercourse with the victim.The prosecutor, Inspector Emmanuel Kumi, told the court that David Adofo's cup became full on November 18, 2012 when in one of his sexual escapades with the girl he was caught by the aunt of the victim.According to the prosecution, at about 10:30pm on that day, Adofo sneaked into the room of the victim to have sexual intercourse with her while she was asleep with her aunty, Agnes, who was suffering from blindness.Inspector Kumi said the girl's aunt, who was awaken by the unusual sexual noise on the bed became suspicious and decided to ascertain what was happening.She managed to detect the presence of the convict in the room through her sense of smell and therefore went to block the entrance of the room to prevent David Adofo from escaping before she raised the alarm.Prosecution narrated that the convict pushed Agnes down and ran away from the room after sensing danger.The mother of the victim was subsequently informed about the incident and she later made a report to the police leading to the arrest of the convict.