Osano, who is capable of playing either in defence or midfield, made his debut for Reading in a 3-2 FA Cup Replay victory against West Bromwich Albion in January 2006. His chances were limited that season at Reading, with Osano mainly appearing in youth and reserve games for 'The Royals'.

After making an appearance from the bench in Reading's pre-season game at Nene Park in 2006, Curtis went out on loan to Conference side Aldershot Town. During his spell at 'The Shots', Curtis made nine appearances, including one substitute appearance against Rushden & Diamonds in a game won 1-0 by Aldershot.

On his return to Reading, Osano made an appearance in another FA Cup 3-2 victory, this time against Birmingham City in January 2007, subsequently Curtis was loaned out to Woking for the remainder of the season. Curtis impressed with his quality down the right hand side in both defence and attack during the 2007-08 season.

During the 2008-09 season Curtis was an ever present for the first 39 league games, until injury kept him out of the final games of the season. He scored his debut goal for the club in the 4-0 victory at Altrincham.

He showed his flexibility by moving to a role in the centre of defence for a period in the middle of the season, before reverting to his right back role. His performances won him the Diamonds Supporters' Player of the Season award, and the Diamond Minors' Player of the Season award.

During the 2009-10 season he once again played at both full-back and centre-back, and his efforts were rewarded with a call-up to the England C squad for their game against Poland Under-23's in Grodzisk Wielkopolski in November 2009.