Marika Tachibana from Nisekoi
Tanning nude on the beach on her back and with her eyes closed.
Here are some linked for references:
http://nisekoi.wikia.com/wiki/Marika_Tachibanahttps://danbooru.donmai.us/posts?tags=tachibana_marika The official art I found for her didn't have that many full body shots, so I included a danbooru link as well.
Thanks to whoever picks this up.