She lost 2k on horse racing, what a wonderful senpai. Asumi's stack of cash for winning seemed to be made of 10k yen notes, which means she needs at least 30 of those to get back the 300k that Senpai lost. And I'ma be honest, that stack does not look like it holds much more than 30 bills in it, so that feels like its just a small win in the grand scheme of things, but who knows, maybe it has way more than that.
Also as a sidenote geez when did the Yen change so much in value. A few years ago you just needed to divide the yen by 100 to get usd (100 to 1), but apparently last month it hit 160 to 1??? Currently sitting around 150 to 1, which is still wild.