USD/JPY is around 153.00, well up from late Friday levels circa 152.30 but down from a high circa 153.30 an hour or so ago.
The news, ICYMI, is that the ruling coalition (LDP/Komeito) lost their majority.
Earlier:
Its likely they'll bring a third party into the coalition and continue to govern but the yen has been hit due to a perception that policy normalisation may face political pressure to proceed more slowly. Cost-of-living pressures in Japan are an important political issue, perhaps #1 or close to (after ruling party funding scandals). Its thought a slowing of policy normalisation (rate hikes) may be a price extracted by a third party for agreement to support the LDP. I've heard the opposite argued, that other parties are in favour of BOJ rate hikes. We'll see.
USD/JPY update: