In the last 10 years, there have been a wide variety of studies on TADF-OLEDs because of the unlimited possibilities of TADF molecular design. Further, hyperfluorescence (HP)-OLEDs have been developed since they can realize the compatibility of high efficiency with narrow spectral width, which is ideal for practical display applications. We recently reported advanced HP-OLEDs, demonstrating high OLED performance by optimizing host, TADF, and terminal emitter(TE) molecules. In particular, we focused on the blue-emission, which is capable of showing narrow FWHM and high EL quantum yield. In this talk, we mention the comprehensive design principle for the materials used in HP-OLEDs by focusing on fast T-S upconversion, efficient FRET GSP, and carrier trapping aimed at high-performance blue EL.