what happened in the aftermath?
The raid demonstrated that Japan had too few air bases and not enough aircraft were available for night operations. It was also found that the Toryu fighter was not well suited to intercepting B-29s as it was slower than the bombers, too lightly armed and most aircraft lacked radar.
Bombing of Yawata (June 1944)
The Yawata raid revealed serious shortcomings in Japan's air defenses. While the 19th Air Brigade initially claimed to have shot down eight B-29s and damaged a further four, it was soon determined that only two of the bombers had been destroyed. This loss ratio was considered too low to defeat attacks on the home islands. The raid demonstrated that Japan had too few air bases and not enough aircraft were available for night operations. It was also found that the Toryu fighter was not well suited to intercepting B-29s as it was slower than the bombers, too lightly armed and most aircraft lacked radar. 
who bombed yawata? United States Army Air Forces (USAAF) strategic bombers where is this place that was bombed? Japan
wiki:18124514
Bombing of Yawata (June 1944) [SEP] Aftermath
landing at Saipan on the same day also indicated to Japanese civilians that the war was not going well. In response to the raid Japanese Government ministers urged families living the country's four major cities to evacuate their children to rural areas. The 15/16 June 1944 raid on Yawata marked the beginning of the USAAF's strategic bombing campaign against Japan. The city was struck again by B-29s during daylight and night raids on 20 August, but no serious damage was caused. XX Bomber Command conducted 49 raids from its bases in China and India between June 1944 and March 1945, of which nine were made on targets in the Japanese home islands, but Operation Matterhorn did not achieve its goals.