It is catchphrase of character okada akane in response to her imagining about nemoto hina It comes in 2 variety 1 the initial one was when Akane shocked for the first time and immediately shout γ²γͺββββββ!!! 2 the next appearance in manga was when she saw dildo in sex toy store where she says Hinaβs name (γ²γͺγ...) while having empty eyes