bohegao

A variant of the ahegao Saikawa Riko from Kobayashi-san Chi no Maidragon makes when getting attention (which she interprets romantically, even if it's sometimes not really meant that way) from her love interest Kanna Kamui. Also known as "Kannagasm".

The facial expression is a typical ahegao (full-face blush, rolled-up eyes, raised eyebrows, goofy smile) with hands on her cheeks, a heart symbol in the mouth and the eponymous "boheeeeee" (a sound effect for a scream of exhilaration).