From Wiktionary, the free dictionary
Borrowed from Hokkien 落氣 / 落气 (làu-khùi, “to lose face”).
lau kui (comparative more lau kui, superlative most lau kui)
- (colloquial, Singapore) Embarrassing, shameful
2004, Bukit Ho Sweerean, soc.culture.singapore (Usenet):You think you are going for a vacation izzit? No wonder our athletes thought like this and we lost miserably. So lau kui.