This is the 6830th most frequent Japanese word.
ブカブカ
"ブカブカ" means "baggy" or "loose-fitting."
'ブカブカ' describes the loose fitting of shoes in this context.
その靴は私にブカブカです。
Those shoes are too loose for me.
'ブカブカ' refers to the oversized nature of the jacket.
彼はブカブカのジャケットを着ている。
He is wearing a baggy jacket.
'ブカブカ' conveys the looseness making it prone to falling off.