It's a custom for folks to bring back "omiyage" when they return from a trip. Kana and Nemu go shopping for some stuff to bring back to Anise and Anpan but sneak a little something in for themselves!
Comic Transcription
Hawaiian Ai - Omiyage
Panel 1: Kana and Nemu are shopping for omiyage before they leave Hawaii and head back home. Kana holds up a t-shirt and Nemu looks at it.
Kana: This shirt is so funny! This is our proof that we've been to Hawaii!
Panel 2: Kana holds up a can of Spam and a musubi mold.
Kana: Can't get the musubi mold without the spam!
Panel 3: Kana strums a ukulele and Nemu watches in delight!
Kana: Ooh - cute! Ani's gonna love this!
Panel 4: Kana holds up a box of Mac Nutty's Hawaiian Macadamia Nut Chocolates and Nemu gets excited!
Kana: And of course... you and I can share these!
Nemu: Ooh! Nutty chocos! Nemu love!