Another comment explained what it is but to explain where the name comes from, you remember those capsule machines where you had to collect all the toys? Those were called gachapon machines, often shortened to just gacha (i might be slightly wrong on a little bit of the words, but they are the capsule machines)
Another comment explained what it is but to explain where the name comes from, you remember those capsule machines where you had to collect all the toys? Those were called gachapon machines, often shortened to just gacha (i might be slightly wrong on a little bit of the words, but they are the capsule machines)