Ikee's teammate Satomi Suzuki shared in her 4x100 metres medley relay success soon after defending her 50m breaststroke title, while Shinri Shioura won the blue riband Men's 100m freestyle to give Japan a total of 17 Golds.
China kept pace through multiple medallists of their own, with Xu Jiayu completing a backstroke sweep in the 200m for his fourth Gold, while Wang Jianjiahe claimed an emphatic victory in the 800m freestyle for a Women's distance double.
The Chinese finished the night with 16 Golds, but still have Sun Yang looking to complete his 200m-400m-800m-1,500m sweep in the longest of the freestyle races today.
With the Tokyo Olympics only two years away however, Ikee will outshine even multiple Olympic and world champion Sun for meet honours if she can secure a sixth Gold in the 50m freestyle on the final night in Jakarta.
Singapore's Olympic champion Joseph Schooling continued his lonely stand against Japanese and Chinese hegemony in the Jakarta pool with a second Gold in butterfly, adding the 50m title to the 100m Gold he won on Wednesday.
It was a close run thing, however, and the 23-year-old was pushed right to the end by China's Wang Peng, winning by four hundredths of a second in 23.61.
World champion Xu could hardly have done more for China in Jakarta and leapt onto the lane ropes to celebrate after an emphatic victory in 1.53.99s.
He added the 100m backstroke title to the 50m and 100m Golds he already had to his name.