This is the first volume of Kazuya Minekura's awesome SAIYUKI, although this volume itself is probably the worst. That's not to say it's bad: it introduces us to the unconventional group of pilgrims known as the Sanzo-ikkou, made up of Genjyo Sanzo, a smoking, drinking, murderous priest, Son Goku, a 500-year-old monkey god who acts like a hungry kid, Sha Gojyo, a lecherous kappa, and Cho Hakkai, the always-smiling converted youkai. It's probably the characters that will get you interested at this point, although their quest is also introduced: they are journeying west in order to prevent the revival of the demon Gyumaoh.
However, if you're interested in SAIYUKI (and I really can't recommend this series highly enough) then my advice would be to buy 1 and 2 in one go. Although 1 is good, volume 2 is EXCELLENT and is, in my opinion, the start of the series itself. Volume 1 feels a bit more like an introduction. That saying, it has some great moments (deducting points from a youkai assassin for his every fault) and if you read this, it will get you started on something you really won't want to stop reading!