Matplotlib: changing xticks font with fontproperties name only applies to first xtick

I'm trying to plot a bar graph where the xtick labels are in Japanese.

After first getting a RuntimeWarning: Glyph <some number> missing from current font. I found xticks's argument fontproperties. Using it as shown in below minimal example, the first of the xtick labels is properly shown in the font I specified, but all following labels are still the missing character rectangles (see image).

import pandas as pd
import matplotlib.pyplot as plt
import matplotlib.font_manager as fm

fprop = fm.FontProperties(fname='NotoSansCJKjp-Regular.otf')

d = {'a': {'ほげイ': 5250.0,
  'ほげロ': 1497.0,
  'ほげハ': 810.0},
 'b': {'ほげイ': 1707.0,
  'ほげロ': 507.0,
  'ほげハ': 305.0}}

df_foo = pd.DataFrame.from_dict(d)

df_foo.plot(kind='bar')
plt.xticks(fontproperties=fprop, fontsize=15)
plt.show()

Here's an image of the output.

Any idea why this happens or how the font of all xtick labels can be specified?

Thanks in advance for any pointers.